NZ707774B2

NZ707774B2 - Gpc3-targeting drug which is administered to patient responsive to gpc3-targeting drug therapy

Info

Publication number: NZ707774B2
Application number: NZ707774A
Authority: NZ
Inventors: Jun Amano; Mikiko Nakamura; Toshihiko Ohtomo; Chen Yachi
Original assignee: Chugai Seiyaku Kabushiki Kaisha; F Hoffmann La Roche Ag; F Hoffmannla Roche Ag
Priority date: 2012-12-21
Filing date: 2013-12-24
Publication date: 2021-02-02

Abstract

Disclosed is a method for determining the efficacy of GPC3-targeted therapeutic agent therapy for a patient or against a cancer in the patient, prior to receiving GPC3-targeted therapeutic agent therapy, or for determining whether to continue GPC3-targeted therapeutic agent therapy for a patient, wherein the method includes a step of monitoring the free GPC3 concentration in a biological specimen isolated from a patient prior to receiving GPC3-targeted therapeutic agent therapy and/or a patient having received GPC3-targeted therapeutic agent therapy, and determining the GPC3-targeted therapeutic agent therapy to be effective, or determining to continue the GPC3-targeted therapeutic agent therapy, when the free GPC3 concentration is a predetermined value. Also disclosed is a GPC3-targeted therapeutic agent or drug formulation for further administration to a patent for whom GPC3-targeted therapeutic agent therapy has been determined effective, or for whom it has been determined to continue GPC3-targeted therapeutic agent therapy. erein the method includes a step of monitoring the free GPC3 concentration in a biological specimen isolated from a patient prior to receiving GPC3-targeted therapeutic agent therapy and/or a patient having received GPC3-targeted therapeutic agent therapy, and determining the GPC3-targeted therapeutic agent therapy to be effective, or determining to continue the GPC3-targeted therapeutic agent therapy, when the free GPC3 concentration is a predetermined value. Also disclosed is a GPC3-targeted therapeutic agent or drug formulation for further administration to a patent for whom GPC3-targeted therapeutic agent therapy has been determined effective, or for whom it has been determined to continue GPC3-targeted therapeutic agent therapy.

Description

[Document Name] Description [Title of Invention] GPC3-TARGETING DRUG WHICH IS ADMINISTERED TO PATIENT RESPONSIVE TO ARGETING DRUG THERAPY [Technical Field] The present invention provides a method for determining the efficacy of GPC3-targeting drug therapy for cancer in a t or determining the continuation of GPC3-targeting drug therapy for a patient. The present invention also provides a GPC3-targeting drug or a preparation which is to be further administered to a patient for the efficacy of the GPC3-targeting drug therapy has been determined or the continuation of the GPC3-targeting drug y has been determined.

[Background Art] Hepatocellular cancer is reportedly the fifth leading cause of cancer deaths worldwide, ting for approximately 0 deaths each year (Non Patent Literature 1). Most patients with hepatocellular cancer die within 1 year after being diagnosed with the disease.

Unfortunately, hepatocellular cancer cases are frequently diagnosed at a late stage which rarely responds to curative therapies. Still, l treatments including chemotherapy, chemoembolization, ablation, and proton beam therapy are insufficiently effective for such patients. Many patients exhibit recurrence of the e with vascular invasion and multiple intrahepatic metastases, which rapidly progresses to the advanced stage. Their 5-year survival rates are only 7% (Non Patent Literature 2). Patients with cellular cancer amenable to the resection of local foci have relatively good prognosis, though their 5-year survival rates still remain at a level of 15% and 39% (Non Patent Literature 3). Thus, there has been a demand in the art for novel therapy for such a malignant disease cellular .

Hepatocellular cancer is reportedly responsible for more than 90% of primary liver cancer cases in Japan.

Medical s for treating such hepatocellular cancer include, for example, chemotherapy-based transcatheter arterial embolization (TAE) therapy, which es inducing the selective necrosis of the hepatocellular cancer by the injection of a mixture of an oil-based contrast medium (Lipiodol), an anticancer agent, and an obstructing substance (Gelfoam) into the hepatic artery (which serves as a nutrient supply pathway to the tumor) resulting in the obstruction of the nutrient artery. In addition, invasive approaches are used, such as percutaneous ethanol injection, percutaneous microwave coagulation therapy, and requency ablation. Also, clinical trials have been conducted on systemic chemotherapy using chemotherapeutic agents such as fluorouracil (5-FU), uracil-tegafur (UFT), mitomycin C (MMC), mitoxantrone (DHAD), adriamycin (ADR), epirubicin (EPI), and cisplatin (CDDP) either alone or in combination with interferon (IFN) (Non Patent ture Meanwhile, an orally active form of sorafenib (Nexavar, BAY43-9006) has been approved, which is more advantageously effective than the chemotherapeutic agents described above in such a way that this agent blocks the growth of cancer cells by ting Raf kinase in the Raf/MEK/ERK signal transduction while the agent exerts antiangiogenic effects by targeting VEGFR-2, VEGFR-3, and PDGFR-β tyrosine kinases. The efficacy of sorafenib has been studied in two phase-III multicenter ocontrolled trials enib HCC Assessment Randomized Protocol ) trial and Asia-Pacific trial) targeting advanced hepatocellular cancer. Sorafenib was confirmed to prolong survival durations, with HR of 0.68, in both of these trials. In the SHARP trial, sorafenib prolonged the survival duration to 10.7 months versus 7.9 months with the placebo. In the Asian trial, this agent prolonged the survival duration to 6.5 months versus 4.2 months with the placebo. The agent, however, had a low objective response rate and showed no prolongation of a time to symptomatic ssion, though the agent prolonged a time to tumor progression (5.5 months versus 2.8 months in the European and American trial and 2.8 months versus 1.4 months in the Asian trial) on the images. The Asian cohorts exhibited a short duration of life prolongation, which is probably because their treatments were started at a slightly later stage during the disease process in the Asian region compared with Europe and the United States (Non Patent Literatures 5 and 6).

As liver cancer progresses, its specific symptoms ated with liver dysfunction are generally observed, such as anorexia, weight loss, general malaise, le right hypochondrial mass, right hypochondrial pain, sense of abdominal fullness, fever, and jaundice. The chemotherapeutic agents (e.g., sorafenib), r, have complications to be overcome, including their inherent adverse ons such as diarrhea or constipation, anemia, ssion of the immune system to cause infection or sepsis (with lethal severity), hemorrhage, cardiac toxicity, hepatic toxicity, renal toxicity, anorexia, and weight loss.

Although particular early-stage symptoms are not initially observed in liver cancer, its specific symptoms associated with liver dysfunction, such as anorexia, weight loss, general malaise, le right hypochondrial mass, right hypochondrial pain, sense of abdominal fullness, fever, and jaundice, are generally observed with progression of the liver . According to al ation, such symptoms are enhanced by use of the chemotherapeutic agents. For example, anorexia in a patient with detectable liver cancer cells and symptoms such as weight loss associated with or independent of the anorexia may be more ed by the administration of the herapeutic agents to the patient than without the use of the chemotherapeutic agents. In some cases, the use of the chemotherapeutic agents must be tinued for the patient having such symptoms. These enhanced symptoms are impediments to treatments with the chemotherapeutic agents. Thus, there has been a demand for the establishment of excellent therapy from the viewpoint of, for example, improving therapeutic effects or improving QOL of patients to be treated.

Glypican 3 (GPC3) is frequently expressed at a high level in liver cancer and as such, seems to be useful in the identification of its functions in liver cancer or as a therapeutic or diagnostic target of liver cancer.

Under the circumstances described above, drugs are under development with GPC3 as a therapeutic target of liver cancer. A liver cancer drug comprising an anti- GPC3 antibody as an active ingredient has been developed, the antibody having antibody-dependent cellular cytotoxicity (hereinafter, referred to as "ADCC") activity and/or complement-dependent cytotoxicity (hereinafter, referred to as "CDC") activity against cells expressing GPC3 (Patent Literature 1). Also, a GPC3-targeting drug comprising a humanized anti-GPC3 antibody having ADCC activity and CDC activity as an active ingredient has been developed (Patent Literature 2). Further GPC3-targeting drugs have been developed, which comprise a humanized anti-GPC3 antibody with ed ADCC ty t Literatures 3 and 4) or an anti-GPC3 antibody having ADCC activity and CDC activity as well as improved plasma dynamics (Patent Literature 5).

These anti-GPC3 antibodies in combination y with the chemotherapeutic agents such as sorafenib have been found to attenuate the adverse reactions, for example, t about by the sole therapy of the chemotherapeutic agents (e.g., sorafenib) and also found to exhibit synergistic effects based on these agents t Literature 6). Accordingly, excellent methods for treating liver cancer are in the process of being established using GPC3-targeting drugs as the nucleus from the viewpoint of, for example, improving therapeutic effects or improving QOL of patients to be treated.

Meanwhile, GPC3-targeting s for diagnosing liver cancer are also under development. GPC3 is known to be expressed on cell surface and processed, at the particular site, by convertase, phospholipase D, Notum or ified mechanism (Non Patent Literature 7 and 8) during or after expression on cell surface. By use of such a phenomenon, a diagnostic agent or a diagnostic method for liver cancer has been developed, which involves an antibody capable of binding to an epitope in a soluble form of GPC3 secreted into the plasma of a patient after processing (Patent Literature 7). Also, a diagnostic agent or a stic method for liver cancer has been developed, which involves an antibody capable of g to an epitope in an anchored form of GPC3 still existing on cell surface after processing in a tissue preparation or the like isolated from a patient (Patent ture 8). These diagnostic agents or diagnostic methods, however, are means for ing the presence of liver cancer in a patient to be tested. Neither a method for determining the efficacy of GPC3-targeting drug therapy for a patient treated with the GPC3-targeting drug therapy nor a method for determining the continuation of argeting drug therapy for the patient has been known yet.

References cited herein are as listed below. The contents described in these literatures are orated herein by reference in their entirety. It should be noted that none of these literatures are admitted to be the prior art to the present ion.

[Citation List] [Patent Literature] [Patent Literature 1] WO2003/000883 [Patent ture 2] WO2006/006693 [Patent Literature 3] WO2006/046751 [Patent Literature 4] WO2007/047291 [Patent Literature 5] WO2009/041062 t Literature 6] WO2009/122667 [Patent Literature 7] WO2004/038420 [Patent Literature 8] WO2009/116659 [Non Patent Literature] [Non Patent Literature 1] Llovet JM, Burroughs A, Bruix J; Lancet (2003), 362, 1907-17 [Non Patent Literature 2] Bosch FX, Ribes J, Cleries R; Gastroenterology (2004), 127, S5-16 [Non Patent Literature 3] Takenaka K, Kawahara N, Yamamoto K, Kajiyama K, Maeda T, a H, Shirabe K, Nishizaki T, Yanaga K, Sugimachi K; Arch Surg (1996), 131, 71-6 [Non Patent Literature 4] Yeo W, Mok TS, Zee B, Leung TW, Lai PB, Lau WY, Koh J, Mo FK, Yu SC, Chan AT, Hui P, Ma B, Lam KC, Ho WM, Wong HT, Tang A, Johnson PJ; J Natl Cancer Inst (2005), 97, 1532-8 [Non Patent Literature 5] Llovet J, Ricci S, Mazzaferro V, Hilgard P, Gane E, et al. Sorafenib in advanced hepatocellular carcinoma. New Eng. J. Med. (2008) 359, 378-90 [Non Patent Literature 6] Cheng AL, Chen Z, Tsao CJ, Qin S, Kim JS, et al. Efficacy and safety of sorefanib in patients in the Asia-Pacific region with advanced cellular carcinoma: a phase III randomized, blind , placebo- controlled trial. Lancet Oncol. (2009) 10, -34 [Non Patent Literature 7] De Cat B, Muyldermans S-Y, Coomans C, Degeest G, Vanderschueren B, et al. Processing by proprotein convertases is required for an-3 modulation of cell survival, Wnt ing, and gastrulation nts. J. Cell. Biol. (2003) 163, 625- [Non Patent Literature 8] Traister A, Shi W and Filmus J.

Mammalian Notum induces the release of glypicans and other GPI-anchored proteins from the cell surface.

Biochem. J. (2008) 410, 503-511 ry of Invention] ical Problem] The present invention has been made in light of the situations as described above, and an object of the present invention is to provide a method for ining the efficacy of GPC3-targeting drug therapy for a patient treated with the GPC3-targeting drug therapy or determining the continuation of GPC3-targeting drug therapy for the patient. Another object of the present ion is to provide a GPC3-targeting drug or a preparation which is to be further administered to a patient for which the efficacy of the GPC3-targeting drug therapy has been determined or the continuation of the GPC3-targeting drug y has been determined. ion to Problem] The present inventors have conducted diligent studies under the situations as described above and consequently created a method comprising monitoring a concentration of free GPC3 in a ical sample isolated from a patient treated with GPC3-targeting drug therapy, wherein when the concentration of free GPC3 is a predetermined value or when the concentration of free GPC3 has been increased as a result of receiving the GPC3-targeting drug therapy, the efficacy of the GPC3- targeting drug therapy is determined or the continuation of the argeting drug therapy is determined. The present inventors have also created a GPC3-targeting drug or a preparation which is to be further administered to a patient for which the efficacy of the GPC3-targeting drug therapy has been determined or the continuation of the GPC3-targeting drug therapy has been determined. It has been expected from the previous findings that the concentration of free GPC3 detected in plasma is sed over time with the continuation of the treatment, if the GPC3-targeting drug therapy has efficacy. Surprisingly, the present inventors have found that the concentration of free GPC3 is stabilized or increased, rather than decreased, in plasma isolated from a patient with stable disease that may respond to the GPC3-targeting drug therapy.

More specifically, the t invention provides the following aspects: a method for ining the efficacy of GPC3- targeting drug therapy for cancer in a t or ining the continuation of GPC3-targeting drug therapy for a patient, comprising monitoring a concentration of free GPC3 in a biological sample isolated from the patient before the start of GPC3- targeting drug therapy and/or the patient treated with the GPC3-targeting drug therapy, wherein when the tration of free GPC3 is a predetermined value, the efficacy of the GPC3-targeting drug therapy is determined or the continuation of the GPC3-targeting drug therapy is determined, the method according to [1], wherein the tration of free GPC3 is a concentration in a whole blood sample, a plasma sample, or a serum sample isolated from the patient, the method according to [2], wherein the concentration of free GPC3 in the biological sample isolated from the patient is a tration in the plasma sample or the serum sample, the method according to any of [1] to [3], wherein the predetermined value of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the method according to any of [1] to [4], wherein the concentration of free GPC3 is measured using an immunological method, the method according to any of [1] to [5], wherein the concentration of free GPC3 is larger than that in a biological sample isolated before the start of the GPC3- ing drug therapy from the patient, the method according to any of [1] to [6], wherein the patient shows high expression of GPC3 in an immunohistochemical staining score, the method according to any of [1] to [7], wherein the cancer is liver cancer, the method according to any of [1] to [8], wherein the GPC3-targeting drug is administered to achieve a blood trough level of 200 µg/ml or higher in the cancer patient, the method according to any of [1] to [9], wherein the GPC3-targeting drug comprises an anti-GPC3 antibody as an active ingredient, the method according to [10], wherein the anti-GPC3 antibody has antibody-dependent cellular cytotoxicity (ADCC) activity and/or complement-dependent cytotoxicity (CDC) activity, the method according to [10] or [11], wherein the anti-GPC3 antibody is an anti-GPC3 chimeric antibody or a zed anti-GPC3 antibody comprising any of the following (1) to (5): (1) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 ented by SEQ ID NOs: 4, 5, and 6, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 ented by SEQ ID NOs: 7, 8, and 9, respectively; (2) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 12, 13, and 14, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 15, 16, and 17, tively; (3) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 20, 21, and 22, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 23, 24, and , respectively; (4) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 28, 29, and 30, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 31, 32, and 33, respectively; and (5) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 36, 37, and 38, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 39, 40, and 41, respectively, The method according to any of [10] to [12], wherein the anti-GPC3 antibody comprises any of the following (1) to (6): (1) a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region ented by SEQ ID NO: 51; (2) a heavy chain variable region selected from the group of heavy chain variable s ented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region selected from the group of light chain variable regions represented by SEQ ID NOs: 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, and 66; (3) a heavy chain le region represented by SEQ ID NO: 67 and a light chain variable region represented by SEQ ID NO: 68; (4) a heavy chain variable region represented by SEQ ID NO: 69 and a light chain variable region represented by SEQ ID NO: 70; (5) a heavy chain variable region ented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 72; and (6) a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 73, the method according to [10], wherein the GPC3- targeting drug ses an anti-GPC3 antibody conjugated with a cytotoxic substance, a GPC3-targeting drug which is to be administered to a cancer t having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient before the start of GPC3-targeting drug therapy, a GPC3-targeting drug which is to be further administered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of argeting drug therapy, the drug according to [15] or [16], wherein the concentration of free GPC3 is a concentration in a whole blood sample, a plasma , or a serum sample isolated from the cancer patient, the drug according to [17], wherein the concentration of free GPC3 in the biological sample isolated from the cancer patient is a concentration in the plasma sample or the serum sample, the drug according to any of [15] to [18], wherein the predetermined value of free GPC3 ranges from 0.1 ng/mL to 60 ng/mL, the drug according to any of [15] to [19], wherein the concentration of free GPC3 is measured using an logical method, the drug according to any of [15] to [20], wherein the concentration of free GPC3 has been increased as a result of receiving the GPC3-targeting drug therapy, the drug ing to any of [15] to [21], wherein the patient shows high expression of GPC3 in an immunohistochemical ng score, the drug according to any of [15] to [22], wherein the cancer patient is a liver cancer patient, the drug according to any of [15] to [23], wherein the GPC3-targeting drug is administered to achieve a blood trough level of 200 µg/ml or higher in the cancer patient, the drug according to any of [15] to [24], wherein the GPC3-targeting drug comprises an anti-GPC3 dy as an active ingredient, the drug according to [25], wherein the anti-GPC3 antibody has antibody-dependent cellular cytotoxicity (ADCC) activity and/or complement-dependent cytotoxicity (CDC) activity, the drug according to [25] or [26], wherein the PC3 antibody is an anti-GPC3 chimeric antibody or a humanized anti-GPC3 antibody comprising any of the following (1) to (5): (1) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 4, 5, and 6, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 7, 8, and 9, respectively; (2) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 ented by SEQ ID NOs: 12, 13, and 14, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 15, 16, and 17, respectively; (3) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 20, 21, and 22, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 23, 24, and , respectively; (4) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 28, 29, and 30, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 31, 32, and 33, respectively; and (5) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 36, 37, and 38, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 39, 40, and 41, respectively, the drug according to any of [25] to [27], wherein the anti-GPC3 antibody comprises any of the following (1) to (6): (1) a heavy chain variable region ed from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region represented by SEQ ID NO: 51; (2) a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region selected from the group of light chain variable s represented by SEQ ID NOs: 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, and 66; (3) a heavy chain variable region represented by SEQ ID NO: 67 and a light chain variable region represented by SEQ ID NO: 68; (4) a heavy chain variable region represented by SEQ ID NO: 69 and a light chain variable region represented by SEQ ID NO: 70; (5) a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region ented by SEQ ID NO: 72; and (6) a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region ented by SEQ ID NO: 73, the drug according to [25], wherein the GPC3- targeting drug comprises an anti-GPC3 antibody conjugated with a cytotoxic substance, a preparation for GPC3-targeting treatment, comprising an instruction stating that the preparation is to be further administered to a cancer patient having a predetermined value of a tration of free GPC3 in a biological sample isolated from the cancer patient before the start of GPC3-targeting drug therapy, a preparation for GPC3-targeting treatment, comprising an instruction stating that the preparation is to be further administered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of GPC3-targeting drug therapy, the preparation according to [30] or [31], n the tration of free GPC3 is a concentration in a whole blood sample, a plasma sample, or a serum sample isolated from the cancer patient, the ation according to [32], wherein the concentration of free GPC3 in the biological sample isolated from the cancer patient is a concentration in the plasma sample or the serum , the preparation according to any of [30] to [33], wherein the predetermined value of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the preparation according to any of [30] to [34], wherein the concentration of free GPC3 is ed using an immunological method, the preparation according to any of [30] to [35], wherein the concentration of free GPC3 has been increased as a result of receiving the GPC3-targeting drug therapy, the preparation according to any of [30] to [36], n the patient shows high sion of GPC3 in an immunohistochemical staining score, the preparation according to any of [30] to [37], wherein the cancer patient is a liver cancer patient, the preparation according to any of [30] to [38], wherein the GPC3-targeting drug is administered to achieve a blood trough level of 200 µg/ml or higher in the cancer patient, the preparation according to any of [30] to [39], wherein the GPC3-targeting drug comprises an anti-GPC3 antibody as an active ingredient, the preparation according to [40], wherein the anti- GPC3 antibody has antibody-dependent cellular xicity (ADCC) activity and/or complement-dependent cytotoxicity (CDC) activity, the preparation according to [40] or [41], wherein the anti-GPC3 dy is an anti-GPC3 chimeric antibody or a humanized PC3 antibody comprising any of the following (1) to (5): (1) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 4, 5, and 6, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 7, 8, and 9, respectively; (2) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 12, 13, and 14, tively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 15, 16, and 17, respectively; (3) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 20, 21, and 22, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 23, 24, and , respectively; (4) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 28, 29, and 30, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 31, 32, and 33, respectively; and (5) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 36, 37, and 38, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 39, 40, and 41, respectively, the preparation according to any of [40] to [42], n the PC3 antibody comprises any of the following (1) to (6): (1) a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region represented by SEQ ID NO: 51; (2) a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region ed from the group of light chain variable regions represented by SEQ ID NOs: 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, and 66; (3) a heavy chain variable region ented by SEQ ID NO: 67 and a light chain variable region represented by SEQ ID NO: 68; (4) a heavy chain variable region represented by SEQ ID NO: 69 and a light chain variable region represented by SEQ ID NO: 70; (5) a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 72; and (6) a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 73, the preparation ing to [40], wherein the GPC3- targeting drug comprises an anti-GPC3 dy conjugated with a cytotoxic substance, a method for treating cancer, comprising administering a GPC3-targeting drug to a patient determined by a method ing to any of [1] to [14].

[Effect of ion] According to the present invention, whether GPC3- targeting drug therapy has efficacy or whether GPC3- targeting drug therapy should be ued can be determined conveniently and accurately. This can improve the s of the GPC3-targeting drug therapy and improve QOL of a patient to be treated. As a result, the better treatment of cancer is achieved.

[Brief Description of Drawings] [] is a diagram showing the histochemical staining images of tissues evaluated as having high expression in a staining score of GPC3-IHC (staining method 1). The numeral shown in the upper part of each ng image represents a patient number. [] is a diagram showing the histochemical staining images of tissues evaluated as being negative or having low expression in a staining score of GPC3-IHC (staining method 1). The numeral shown in the upper part of each staining image represents a patient number. [ is a diagram showing the durations of GC33 administration to 20 cases. Each cycle involves four doses of GC33 (administered once a week). [ is a diagram showing a difference in progression-free survival duration among a patient group from which s divided into two groups (with a total score of 7 or higher and with a total score lower than 7) according to a staining method based on epitope val using autoclaving were isolated. The solid line represents the progression-free survival duration of the group with a total score of 7 or higher (9 cases). The broken line represents the progression-free survival duration of the group with a total score lower than 7 (7 cases). The hazard ratio of the group with a total score of 7 or higher to the group with a total score lower than 7 was 0.376 (95% confidence al: 1.227, p = 0.0852). [] is a diagram showing the correlation between the concentration of free GPC3 detected in serum and the GPC3-IHC score of tumor tissues, in a group evaluated as having high expression of GPC3. The ordinate shows the serum concentration ) of free GPC3. The abscissa shows the number of lapsed days (day) after the start of GPC3-targeting drug therapy. [] is a diagram showing the ation n the concentration of free GPC3 detected in serum and the HC score of tumor tissues, in a group ted as having low sion of GPC3 or being negative. The ordinate shows the serum concentration (ng/mL) of free GPC3. The abscissa shows the number of lapsed days (day) after the start of GPC3-targeting drug therapy. [] is a diagram showing the correlation between the concentration of free GPC3 in serum isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival duration of the patients. The ordinate shows a survival rate. The abscissa shows progression-free survival duration (day) after the start of GPC3-targeting drug therapy. The solid line represents the progressionfree survival duration of a group having a able level of free GPC3 (6 cases). The broken line rep resents the progression-free survival duration of a group having a GPC3 level below the measurement limit (0.4 ng/mL) (14 cases). [] is a diagram showing the correlation between the concentration of free GPC3 in serum isolated from serum collected from patients during a test period (including before and after the start of GPC3-targeting drug therapy) and the progression-free survival duration of the patients. The ordinate shows a survival rate.

The abscissa shows progression-free al on (day) after the start of GPC3-targeting drug y.

The solid line represents the ssion-free al duration of a group having a measurable level of free GPC3 (9 cases) in serum isolated from serum collected from the patients before or during GPC3-targeting drug therapy. The broken line represents the progression-free survival duration of a group having a GPC3 level below the measurement limit (0.4 ng/mL) (both before and after the start of GPC3-targeting drug therapy) (11 cases) in serum isolated from serum collected from the patients treated with the therapy. [] is a diagram showing the correlation between the concentration of free GPC3 in serum isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival on of the patients. The ordinate shows a survival rate. The abscissa shows progression-free survival duration (day) after the start of GPC3-targeting drug therapy. The solid line represents the progressionfree survival duration of a group having a measurable level of free GPC3 (8 cases). The broken line represents the progression-free survival duration of a group having a GPC3 level below the measurement limit (0.4 ng/mL) (19 cases). The hazard ratio of the group with a detectable level of GPC3 to the group with a GPC3 level below the detection limit was 0.265 (95% confidence interval: 0.077-0.914, p = ). [] is a diagram showing the correlation between the concentration of free GPC3 in serum isolated from serum collected from patients during a test period (including before and after the start of GPC3-targeting drug therapy) and the progression-free survival duration of the patients. The ordinate shows a al rate.

The abscissa shows progression-free survival duration (day) after the start of GPC3-targeting drug y.

The solid line represents the progression-free survival duration of a group having a measurable level of free GPC3 (13 cases) in serum isolated from serum collected from the ts before or during GPC3-targeting drug therapy. The broken line represents the progression -free survival duration of a group having a GPC3 level below the measurement limit (0.4 ng/mL) (both before and after the start of GPC3-targeting drug therapy) (14 cases) in serum isolated from serum collected from the patients d with the therapy. The hazard ratio of the group with a detectable level of GPC3 to the group with a GPC3 level below the detection limit was 0.283 (95% confidence interval: 0.112-0.715, p = 0.0038). [] is a diagram showing the ation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival duration of the patients in a group with the serum concentration of free GPC3 lower than the median value (1129.7 pg/mL). The solid line represents the progression-free survival on of a o group (34 cases). The broken line represent s the progression-free survival duration of a group with a putative trough level of GC33 lower than the median value (low-GC33-exposed group: 19 cases). The dotted line represents the progression-free survival duration of a group with a putative trough level of GC33 equal to or higher than the median value (high-GC33-exposed group: 34 cases). The median value of the progression-free survival duration was 83 days for the placebo group, 43.5 days for the low- GC33-exposed group, and 124 days for the high-GC33- exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.803 (p = 0.397), whereas the hazard ratio of the high-GC33-exposed group to the 33-exposed group was 0.425 (p = 0.010). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival on of the patients in a group with the serum concentration of free GPC3 equal to or higher than the median value 7 pg/mL). The solid line represents the progression-free survival duration of a placebo group (24 . The broken line represents the progression-free survival duration of a low-GC33-exposed group (40 cases). The dotted line represents the progression-free survival duration of a high-GC33-exposed group (24 cases). The median value of the progressionfree survival duration was 44 days for the placebo group, 46.5 days for the 33-exposed group, and 87 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the o group was 0.510 (p = 0.036), whereas the hazard ratio of the high-GC33- exposed group to the 33-exposed group was 0.572 (p = 0.056). [] is a diagram showing the correlation between the serum concentration of free GPC3 ed from serum collected from ts before the start of GPC3-targeting drug therapy and the overall survival duration of the patients in a group with the serum concentration of free GPC3 lower than the median value (1129.7 pg/mL). The solid line represents the overall al duration of a placebo group (34 cases). The broken line represents the overall survival duration of a low-GC33-exposed group (19 cases). The dotted line represents the overall survival duration of a high-GC33- exposed group (34 cases). The median value of the overall survival duration was 203 days for the placebo group, 86 days for the low-GC33-exposed group, and 295 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.590 (p = 0.200), whereas the hazard ratio of the high- GC33-exposed group to the low-GC33-exposed group was 0.329 (p = 0.008). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the overall al duration of the patients in a group with the serum concentration of free GPC3 equal to or higher than the median value (1129.7 pg/mL). The solid line represents the overall survival duration of a placebo group (24 cases). The broken line represents the overall survival duration of a low-GC33-exposed group (40 cases). Th e dotted line represents the overall survival duration of a high-GC33-exposed group (24 cases). The median value of the overall survival duration was 121 days for the o group, 177 days for the low-GC33-exposed group, and 308 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.303 (p = 0.005), whereas the hazard ratio of the C33-exposed group to the low-GC33-exposed group was 0.280 (p = 0.002). [] is a m showing the correlation between the serum tration of free GPC3 isolated from serum collected from patients before the start of argeting drug therapy and the progression-free survival duration of the patients in a group with the serum tration of free GPC3 higher than 175 pg/mL.

The solid line represents the progression-free survival duration of a placebo group (51 . The broken line represents the progression-free survival duration of a 33-exposed group (56 . The dotted line represents the progression-free survival on of a high-GC33-exposed group (47 cases). The median value of the progression-free survival duration was 51 days for the placebo group, 45 days for the low-GC33-exposed group, and 124 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.597 (p = 0.0184), whereas the hazard ratio of the high-GC33-exposed group to the low-GC33-exposed group was 0.439 (p = 0.0003). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the l survival duration of the patients in a group with the serum concentration of free GPC3 higher than 175 pg/mL. The solid line represents the overall survival duration of a placebo group (51 cases). The broken line represents the overall survival duration of a low-GC33-exposed group (56 . The dotted line represents the overall survival duration of a high-GC33-exposed group (47 cases). The median value of the overall survival duration was 203 days for the placebo group, 141 days for the low-GC33- exposed group, and 308 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.402 (p = 0.0037), s the hazard ratio of the high-GC33-exposed group to the low- GC33-exposed group was 0.238 (p = <0.0001). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival on of the patients in a group with the serum tration of free GPC3 lower than the median value (1161.5 pg/mL). The solid line represents the progression-free survival duration of a placebo group (31 cases). The broken line represents the ssion-free survival duration of a low-GC33-exposed group (20 cases).

The dotted line represents the progression-free survival duration of a high-GC33-exposed group (36 cases). The median value of the progression-free survival on was 82 days for the placebo group, 43 days for the low- GC33-exposed group, and 124 days for the high-GC33- exposed group. The haza rd ratio of the C33-exposed group to the placebo group was 0.713 (p = 0.197), whereas the hazard ratio of the high-GC33-exposed group to the low-GC33-exposed group was 0.392 (p = 0.004). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival on of the patients in a group with the serum concentration of free GPC3 equal to or higher than the median value (1161.5 pg/mL). The solid line represents the progression-free survival duration of a placebo group (27 . The broken line represents the progression-free survival duration of a low-GC33-exposed group (39 cases). The dotte d line ents the progression-free survival duration of a high-GC33-exposed group (22 cases). The median value of the progressionfree al duration was 45 days for the placebo group, 47 days for the low-GC33-exposed group, and 87 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.588 (p = 0.092), whereas the hazard ratio of the high-GC33- exposed group to the low-GC33-exposed group was 0.626 (p = 0.116). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum ted from patients before the start of argeting drug therapy and the overall survival duration of the patients in a group with the serum concentration of free GPC3 lower than the median value (1161.5 pg/mL). The solid line represents the overall survival duration of a placebo group (31 cases). The broken line represents the overall survival duration of a low-GC33-exposed group (20 cases). The dotted line represents the overall survival duration of a high-GC33- d group (36 cases). The median value of the overall survival duration was 203 days for the placebo group, 86 days for the 33-exposed group, and 295 days for the high-GC33-exposed group. Th e hazard ratio of the high-GC33-exposed group to the placebo group was 0.508 (p = 0.100), whereas the hazard ratio of the high- GC33-exposed group to the low-GC33-exposed group was 0.287 (p = 0.002). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum ted from patients before the start of GPC3-targeting drug therapy and the overall survival duration of the patients in a group with the serum concentration of free GPC3 equal to or higher than the median value 5 pg/mL). The solid line represents the overall survival duration of a placebo group (27 cases). The broken line represents the overall survival duration of a low-GC33-exposed group (39 cases). The dotted line represents the overall al duration of a high-GC33-exposed group (22 cases). The median value of the overall survival duration was 176 days for the placebo group, 177 days for the low-GC33-exposed group, and 291 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.300 (p = 0.022), whereas the hazard ratio of the high-GC33-exposed group to the low-GC33-exposed group was 0.324 (p = 0.005). [] is a diagram showing the correlation between the serum concentration of free GPC3 isolated from serum collected from patients before the start of GPC3-targeting drug therapy and the progression-free survival duration of the patients in a group with the serum concentration of free GPC3 higher than 259.7 pg/mL.

The solid line represents the ssion-free survival duration of a placebo group (50 . The broken line represents the ssion-free survival duration of a low-GC33-exposed group (55 cases). The dotted line represents the progression-free al duration of a high-GC33-exposed group (47 cases). The median value of the progression-free survival duration was 46.5 days for the placebo group, 45.5 days for the low-GC33-exposed group, and 124 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.567 (p = 0.010), whereas the hazard ratio of the high-GC33-exposed group to the low-GC33- exposed group was 0.467 (p = 0.0009). [] is a diagram showing the correlation n the serum concentration of free GPC3 isolated from serum collected from patients before the start of argeting drug therapy and the overall survival duration of the patients in a group with the serum concentration of free GPC3 higher than 259.7 pg/mL. The solid line represents the l survival duration of a placebo group (50 . The broken line represents the overall survival duration of a low-GC33-exposed group (55 cases). The dotted line represents the overall survival duration of a high-GC33-exposed group (47 cases). The median value of the overall survival duration was 185 days for the placebo group, 156 days for the low-GC33- exposed group, and 308 days for the high-GC33-exposed group. The hazard ratio of the high-GC33-exposed group to the placebo group was 0.414 (p = 0.0043), whereas the hazard ratio of the high-GC33-exposed group to the low- xposed group was 0.304 (p = <0.0001).

The present specification encompasses the contents described in the specification of Japanese Patent Application No. 2012-280304 on which the priority of the present application is based. iption of Embodiments] Definition Chemical terms and technical terms used in relation to the t invention have meanings generally tood by those skilled in the art, unless otherwise defined herein.

Indefinite article In the present ion, the indefinite articles "a" and "an" refer to one or two or more (i.e., at least one) object(s) tically represented by the indefinite articles. For example, "a factor" means one factor or two or more factors.

Amino acid Each amino acid is indicated herein by single-letter code or three-letter code, or both, as represented by, for e, Ala/A, Leu/L, Arg/R, Lys/K, Asn/N, Met/M, Asp/D, Phe/F, Cys/C, Pro/P, Gln/Q, Ser/S, Glu/E, Thr/T, Gly/G, Trp/W, His/H, Tyr/Y, Ile/I, and Val/V.

Amino acid modification An amino acid in the amino acid sequence of an antigen-binding molecule can be modified by an appropriately d method known in the art such as site-directed mutagenesis (Kunkel et al., Proc. Natl.

Acad. Sci. USA (1985) 82, 488-492) or overlap extension PCR. Also, a plurality of s known in the art can be adopted as methods for modifying an amino acid to substitute the amino acid by an amino acid other than natural one (Annu. Rev. Biophys. Biomol. Struct. (2006) , 225-249; and Proc. Natl. Acad. Sci. U.S.A. (2003) 100 (11), 6353-6357). For example, a tRNA -containing cellfree translation system (Clover Direct (Protein Express, an R & D oriented company)) comprising a non-natural amino acid bound with an amber suppressor tRNA complementary to UAG codon (amber codon), which is a stop codon, is also preferably used.

The term "and/or" used herein to represent amino acid modification sites is meant to include every combination appropriately represented by "and" and "or".

Specifically, for e, the phrase "amino acids 43, 52, and/or 105 are substituted" includes the following variations of amino acid cation: (a) position 43, (b) position 52, (c) position 105, (d) positions 43 and 52, (e) positions 43 and 105, (f) positions 52 and 105, and (g) positions 43, 52, and 105.

EU numbering and Kabat numbering ing to a method used in the t invention, amino acid positions ed to antibody CDRs and FRs are defined by the Kabat method (Sequences of Proteins of Immunological Interest, National Institute of Health, Bethesda, Md., 1987 and 1991). When the antigen -binding molecule described herein is an antibody or an antigenbinding fragment, amino acids in variable and nt regions are indicated according to the Kabat numbering and the EU numbering conforming to the Kabat amino acid positions, respectively.

Biological sample In the present invention, the term "biological sample" refers to a sample of a tissue or a fluid ed from a subject. In a non-limiting aspect, examples of such samples include plasma, serum, spinal fluid, lymph, external sections of skin, respiratory tract, intestinal tract, and genitourinary tract, tear, saliva, sputum, milk, whole blood or any blood on, blood tives, blood cells, tumor, nervous tissues, organs or any type of tissue, any sample obtained by lavage (e.g., samples derived from the bronchi), and samples of components constituting cell cultures in vitro.

The concentration of free GPC3 can be measured in a biological sample isolated from a patient. The concentration of free GPC3 may be ed in, for example, a whole blood sample or a blood fraction (e.g., serum or plasma) sample (also referred to as a whole blood sample, a serum sample, or a plasma sample, tively, herein). In a non-limiting aspect, the concentration of free GPC3 in a whole blood sample, a serum sample, or a plasma sample from a patient can be measured using, for example, commercially available Human Glypican-3 ELISA kit (BioMosaics Inc.) or Enzyme-linked Immunosorbent Assay Kit For Glypican 3 (GPC3) (USCN Life Science Inc.) and the whole blood sample, the serum sample, or the plasma sample treated with EDTA.

The term "isolated" refers to causing "artificial" change from a natural state, i.e., shifting and/or removing a naturally occurring substance from its original environment. In the present invention, the term "isolated" means that, for example, a polynucleotide or a polypeptide present in an organism is unisolated, whereas the same polynucleotide or polypeptide thereas is isolated when separated from a material present with the cleotide or the polypeptide in a natural state. A polynucleotide or a polypeptide introduced into an sm by transformation, genetic lation, or any other recombination method is in an isolated state even when t in the organism (regardless of being alive or dead).

Free GPC3 In the present invention, the term "free GPC3" refers to GPC3 unanchored to GPC3-expressing cells and es fragments of secretory GPC3 that can be easily dissociated from GPC3 anchored to GPC3-expressing cells under particular conditions in vivo or in vitro. In a non-limiting aspect, examples of the "free GPC3" can include a polypeptide from the amino terminus to position 358 in GPC3 consisting of the ptide d by SEQ ID NO: 1, a polypeptide from the amino terminus to position 374 in GPC3 consisting of the polypeptide defined by SEQ ID NO: 1, a GPC3 polypeptide liberated by the degradation of a GPI anchor t at the carboxy terminus, and their fragments t ture 7).

Those skilled in the art can appropriately select an approach known in the art for determining the structure of free GPC3. In a non -limiting aspect, a method therefor that may be appropriately used involves, for example, directly detecting free GPC3 present in the serum or the plasma of a patient or a model animal by the method described in Patent Literature 7 and analyzing its structure or involves, for example, allowing an enzyme dissociating free GPC3, such as convertase, phospholipase D, or Notum, to act on GPC3 expressed in cells cultured in vitro, detecting the resulting free GPC3, and analyzing its structure (e.g., J. Cell. Biol. (2003) 163 (3), 625-635).

Method for measuring concentration of free GPC3 The tration of free GPC3 can be measured by one or more methods selected from the group consisting of the following: spectroscopic methods such as nuclear magnetic resonance (NMR) and mass spectrometry (MS); and SELDI(-TOF), MALDI(-TOF), 1D gel-based is, 2D gelbased analysis, liquid chromatography (e.g., highpressure liquid chromatography (HPLC) or low-pressure liquid chromatography (LPLC)), thin-layer chromatography, and based techniques. Examples of appropriate LCMS techniques can include ICAT(R) (Applied Biosystems, Inc.) and iTRAQ(R) (Applied Biosystems, Inc.). Also, a method which involves detecting a further fragment of free GPC3 r digested with an appropriate enzyme may be appropriately adopted.

The assay of free GPC3 can be carried out by a direct or indirect detection method. Free GPC3 can be detected directly or indirectly via the interaction of a ligand or a ligand group with, for example, an enzyme, a bond, a receptor or a transport protein, an antibody, a peptide, an aptamer or an oligonucleotide, or an arbitrary synthetic chemical receptor or compound capable of specifically g to free GPC3. The ligand may be modified with a able label such as a luminescent label, a scent label, or a radioactive label, and/or an affinity tag.

Immunological method Examples of preferred methods for assaying free GPC3 can e immunological methods using an antibody capable of binding to an epitope present in GPC3.

Examples of the immunological s include enzyme immunoassay (ELISA or EIA), fluorescence immunoassay (FIA), mmunoassay (RIA), luminescence immunoassay (LIA), immunoenzymatic technique, fluorescent antibody technique, immunochromatography, immunoturbidimetry, latex turbidimetry, and latex agglutination assay. In the immunological method of the present invention, free GPC3 may be assayed by procedures of manual operation or using an apparatus such as an analyzer.

The immunological method of the present invention can be performed according to, for example, a method known in the art such as sandwich que. For example, a y antibody immobilized on a carrier, a biological sample, and a secondary antibody modified with a labeling material are reacted simultaneously or in order. This reaction forms a complex of the primary antibody immobilized on a carrier, free GPC3, and the secondary antibody modified with a labeling material. The labeling al conjugated with the secondary antibody ned in this complex can be quantified to thereby measure the amount (concentration) of the free GPC3 contained in the ical sample.

In the case of, for example, the enzyme immunoassay, a primary antibody-immobilized microplate, serially d ical samples, a secondary antibody modified with an enzyme such as HRP, a washing buffer, and a solution containing a substrate reactive with the enzyme such as HRP are preferably used. In a non-limiting aspect of assay, the enzyme modifying the secondary antibody is reacted under the m conditions thereof with the substrate. The amount of the resulting enzymatic reaction product can be measured by an l method or the like. In the case of the fluorescence assay, a primary antibody-immobilized optical waveguide, serially diluted biological samples, a secondary antibody ed with a fluorescent material, and a washing buffer may be preferably used. In a nonlimiting aspect of assay, the fluorescent material modifying the secondary antibody can be irradiated with excitation light to thereby emit fluorescence, the intensity of which is then measured.

The radioimmunoassay involves measuring the amount of radiation from a radioactive substance. The luminescence immunoassay es measuring luminescence intensity derived from a scent reaction system.

For example, the immunoturbidimetry, the latex turbidimetry, or the latex agglutination assay involves ing transmitted light or ring light by an endpoint or rate method. The chromatography, for example, which is based on visual observation, involves visually measuring the color of the labeling material appearing on a test line. Alternatively, an instrument such as an analyzer may be appropriately used instead of this visual measurement.

In the immunological method of the present invention, the primary antibody for immobilization on a carrier can be adsorbed or bound to the carrier by a method such as physical adsorption, chemical binding, or a combination thereof. A method known in the art may be appropriately used for lizing the dy by physical adsorption.

Examples of the method include a method which involves contacting the antibody with the carrier by mixing in a solution such as a buffer solution, and a method which involves contacting the dy dissolved in a buffer or the like with the carrier. Alternatively, the antibody may be immobilized onto the carrier by chemical binding.

Examples of the method e a method which es contacting the antibody and the carrier by mixing with a divalent cross-linking reagent such as glutaraldehyde, carbodiimide, imide ester, or maleimide to react the reagent with amino groups, carboxyl groups, thiol groups, aldehyde groups, or hydroxy groups in both the antibody and the carrier. Such immobilization may require treatment for suppressing nonspecific reaction or the l ation or the like of the antibodyimmobilized carrier. In such a case, the aftertreatment of the immobilization can be performed by a method known in the art. Examples of the method include a method which involves g the surface or inner wall of the antibody-immobilized carrier by contacting with, for example, a protein (e.g., bovine serum albumin (BSA), casein, gelatin, egg albumin, or a salt thereof), a surfactant, or a skimmed milk.

In the immunological method of the present invention, the secondary antibody for modification with a labeling material can be adsorbed or bound to the ng al by a method such as physical adsorption, chemical binding, or a combination thereof. A method known in the art may be appropriately used for binding the antibody to the labeling material by physical tion. Examples of the method include a method which involves contacting the antibody with the labeling material by mixing in a solution such as a buffer solution, and a method which es ting the antibody dissolved in a buffer or the like with the labeling material. When the labeling material is, for example, gold colloid or latex, the physical adsorption method is effective. The antibody can be mixed and contacted with the gold colloid in a buffer to obtain a gold colloid-labeled antibody. Alternatively, the antibody may be modified with the labeling material by chemical binding. Examples of the method include a method which involves ting the dy and the labeling material by mixing with a divalent cross-linking reagent such as glutaraldehyde, carbodiimide, imide ester, or maleimide to react the t with amino groups, carboxyl groups, thiol groups, aldehyde groups, or hydroxy groups in both the antibody and the labeling material. When the labeling material is, for example, a fluorescent al, an enzyme, or a chemiluminescent material, the chemical binding method is effective. Such modification may require treatment for suppressing cific reaction or the natural aggregation or the like of the antibody modified with the labeling material.

In such a case, the aftertreatment of the labeling can be performed by a method known in the art. Examples of the method include a method which involves coating the labeling material-bound antibody by contacting with, for example, a protein (e.g., bovine serum albumin (BSA), casein, gelatin, egg albumin, or a salt thereof), a surfactant, or a skimmed milk.

For example, peroxidase (POD), alkaline phosphatase (ALP), β-galactosidase, urease, catalase, e oxidase, lactate dehydrogenase, or e can be used as the labeling material for enzyme immunoassay. For example, fluorescein isothiocyanate, tetramethylrhodamine isothiocyanate, substituted rhodamine ocyanate, dichlorotriazine isothiocyanate, cyanine, or merocyanine can be used for scence immunoassay. For example, tritium, iodine 125, or iodine 131 can be used for radioimmunoassay. For example, a luminol system, a luciferase system, an acridinium ester system, or a dioxetane compound system can be used for luminescence immunoassay. Alternatively, fine particles made of a al such as polystyrene, a styrene-styrene sulfonate copolymer, an acrylonitrile-butadiene-styrene copolymer, a vinyl chloride-acrylic acid ester copolymer, a vinyl e-acrylic acid copolymer, polyacrolein, a styrenemethacrylic acid copolymer, a styrene-glycidyl (meth)acrylate copolymer, a styrene-butadiene copolymer, a methacrylic acid polymer, an acrylic acid polymer, latex, gelatin, liposome, a microcapsule, silica, alumina, carbon black, a metal compound, a metal, a metal colloid, a ceramic, or a ic substance can be used for immunochromatography, immunoturbidimetry, latex turbidimetry, or latex agglutination assay.

A solid-phase carrier in the form of, for example, beads, a microplate, a test tube, a stick, a membrane, or a test pieces made of a material such as polystyrene, polycarbonate, polyvinyltoluene, polypropylene, hylene, polyvinyl chloride, nylon, polymethacrylate, polyacrylamide, latex, liposome, gelatin, agarose, cellulose, Sepharose, glass, a metal, a c, or a magnetic substance can be appropriately used as the carrier in the immunological method of the t invention.

The present invention also provides an assay kit comprising components for use in the immunological method of the present invention. The assay kit comprises at least one type of antibody capable of binding to an epitope present in GPC3. The antibody may be provided in a state immobilized on the r mentioned above or may be provided independently of the carrier. The kit may additionally comprise standard ons of serially diluted free GPC3. The assay kit may further comprise at least one type of antibody capable of binding to an e different from that present in GPC3. Assay principles, etc., for use in the immunoassay kit of the present invention are the same as in the immunological method mentioned above. In the immunoassay kit of the present invention, various aqueous solvents may be used.

Examples of the aqueous solvents include purified water, saline, and various buffers such as tris buffers, phosphate buffers, and phosphate-buffered saline. The pH of this buffer can be appropriately selected from among suitable pHs. The pH value used is not limited and is generally selected within the range of pH 3 to 12.

The immunoassay kit of the present ion may further appropriately contain, in addition to the components mentioned above, one or two or more components selected from ns (e.g., bovine serum albumin (BSA), human serum albumin (HSA), casein, and salts thereof), various salts, various sugars, skimmed milk, s animal sera (e.g., normal rabbit serum), various antiseptics (e.g., sodium azide and otics), ting substances, reaction-promoting substances, sensitivity-increasing substances (e.g., polyethylene glycol), nonspecific reaction-inhibiting nces, and various surfactants such as nonionic surfactants, amphoteric surfactants, and anionic surfactants. The trations of these components contained in the assay reagent are not limited and are preferably 0.001 to 10% (W/V). Particularly preferred concentra tions are appropriately selected within the range of 0.01 to 5% (W/V).

The assay kit of the present invention may be further combined with other reagents, in addition to the components mentioned above. Examples of these other ts include buffers, diluting solutions for biological samples, reagent diluting solutions, reagents ning labeling materials, reagents containing substances that generate signals such as color, reagents containing substances involved in the tion of signals such as color, reagents containing nces for calibration, and ts containing substances for accuracy control.

The immunoassay kit of the present invention can have any form without limitations and may be provided as an integral-type diagnostic kit comprising all of the components constituting the immunoassay kit of the present invention in order to carry out assay conveniently in a short time. Examples of the integraltype diagnostic kit include ELISA kits, fluorescence immunoassay kits, and immunochromatography kits. The ELISA kit form comprises, for example, a primary antibody-immobilized microplate, standard ons of serially diluted free GPC3, a secondary antibody modified with an enzyme such as HRP, a washing , and a substrate solution for the enzymatic reaction. The fluorescence immunoassay kit comprises, for example, a primary antibody-immobilized optical waveguide, standard solutions of serially diluted free GPC3, a secondary antibody modified with a fluorescent material, and a washing buffer. The immunochromatography kit comprises a membrane housed in a reaction cassette. In one exemplary aspect, the primary antibody is immobilized at one end (downstream) of the membrane; a developing solution is placed at the other end (upstream) of the membrane; a pad supplemented with a substrate for the labeling agent is disposed in proximity (downstream) to the developing solution; and a pad mented with the secondary dy labeled as described above is disposed in the central part of the ne.

In the present invention, preferred es of biological samples used for ing the expression level of GPC3 in tissues e test subject-derived preparations. The test subject-derived preparation is preferably a tissue obtained from the test subject, more preferably a liver cancer or hepatocellular cancer tissue of the test subject. The liver cancer or cellular cancer tissue is collected preferably using a biopsy method known in the art. The liver biopsy refers to a method of directly ing a thin long needle into the liver from skin e and collecting liver tissues.

The needling site is typically the intercostal space of the right lower chest. The safety of the needling site is confirmed before operation using an ultrasonic examination apparatus. Then, the needling site is disinfected. A region from the skin to the surface of the liver is subjected to anesthesia. After small incision of the skin at the needling site, a re needle is inserted thereto.

For microscopic observation by transmitted beams, the tissue preparation is sliced to a degree that allows beams of light for use in the microscope to sufficiently penetrate the tissue slice. At a stage prior to the slicing, the tissue preparation is fixed. Specifically, proteins in tissues or cells are coagulated by dehydration or denaturation to thereby rapidly kill the cells tuting the s. The resulting structure is stabilized and insolubilized. First, the tissue preparation to be fixed is cut into a fragment with a size and a shape suitable for the preparation of paraffin-embedded sections by use of a knife such as a surgical knife. Subsequently, the fragment is dipped in a fixative, which is a reagent used for carrying out fixation. Formalin, more preferably neutral buffered formalin, is preferably used as the fixative. The concentration of the neutral ed formalin is appropriately selected according to the characteristics or al properties of the tissue preparation. The tration used may be appropriately changed between 1 and 50%, preferably 5 and 25%, more preferably 10 and 15%.

The fixative with the tissue preparation dipped therein is appropriately degassed using a vacuum pump. For fixation, the tissue preparation is left for several hours in the ve under conditions of ordinary pressure and room temperature. The time required for the fixation can be riately selected within the range of 1 hour to 7 days, preferably 2 hours to 3 days, more preferably 3 hours to 24 hours, further preferably 4 hours to 16 hours. The tissue preparation thus fixed is appropriately dipped in a phosphate buffer solution or the like for additional several hours (which can be appropriately selected within the range of 2 hours to 48 hours, preferably 3 hours to 24 hours, more preferably 4 hours to 16 hours).

Next, sections can be ably prepared by freeze sectioning or in sectioning from the tissue preparation thus fixed. Preferred examples of the freeze sectioning include a method which involves adding tissues into O.C.T. Compound (Miles Inc.), freezing the mixture, and slicing the frozen mixture using a at (frozen section preparation apparatus). In the paraffin sectioning, the fixed tissue preparation is dipped in an embedding agent, which is then solidified to thereby impart thereto uniform and appropriate hardness.

Paraffin can be preferably used as the embedding agent.

The fixed tissue preparation is dehydrated using ethanol.

Specifically, the tissue preparation is dipped in 70% ethanol, 80% ethanol, and 100% ethanol in this order and thereby dehydrated. The time required for the dipping and the number of runs can be appropriately selected within the ranges of 1 hour to several days and 1 to 3 times, respectively. The tissue preparation may be dipped therein at room temperature or 4°C. In the case of dipping at 4°C, a longer g time (e.g., overnight) is more preferred. After replacement of the liquid phase with xylene, the tissue ation is embedded in in. The time required for the replacement of the liquid phase with xylene can be riately selected within the range of 1 hour to several hours. This replacement may be performed at room temperature or 4°C. In the case of replacement at 4°C, a longer ement time (e.g., ght) is more preferred. The time required for the embedding in paraffin and the number of runs can be appropriately selected within the ranges of 1 hour to several hours and 1 to 4 times, tively. This embedding may be performed at room temperature or 4°C. In the case of embedding at 4°C, a longer embedding time (e.g., overnight) is more preferred. Alternatively, the tissue preparation may be ably embedded in paraffin using paraffin embedding apparatus (EG1160, Leica, etc.) that automatically performs paraffin embedding on.

The tissue preparation thus paraffin-embedded is bonded to a block base to prepare a "block". This block is sliced into the desired thickness selected from thicknesses of 1 to 20 µm by use of a microtome. The sliced tissue section is left standing on a glass slide as a permeable support and thereby fixed thereon. In this case, the glass slide coated with 0.01% - lysine (Sigma-Aldrich Corp.) and then dried may be preferably used in order to prevent the tissue section from coming off. The fixed tissue section is dried in air for an appropriate time selected from between several minutes and 1 hour.

Epitope retrieval In a preferred aspect, an epitope in an antigen whose reactivity with an antibody has been ated due to in fixation is retrieved. In the present invention, protease-induced epitope val (PIER) or heat-induced epitope retrieval (HIER) may be applied to the retrieval. In a non-limiting aspect, PIER may be applied to one of "two identifiable tissue preparations" prepared as shown below, while HIER may be applied to the other preparation. In this case, a difference in the degree of staining between these preparations d with antibodies can be digitized.

In a non-limiting aspect, a set of two tissue preparations is prepared, which are prepared as shown in the paragraph "Biological " and attached onto permeable supports. The tissue preparations are desirably two histologically identifiable tissue preparations. The term "identifiable" means that two tissue preparations to be mutually compared are composed of substantially the same cells or tissues in test subject-derived preparations g as origins of the tissue preparations. For example, two tissue preparations prepared as adjacent sections correspond to two identifiable tissue ations. In the present invention as well, the "two identifiable tissue preparations" refer to two tissue preparations prepared as nt sections, unless otherwise specified. In addition, two tissue preparations ed of cells or tissues structurally identifiable between the preparations correspond to "two identifiable tissue preparations", even if the tissue ations are not prepared as adjacent sections. Preferred es of such two tissue preparations composed of cells or tissues structurally identifiable therebetween include (1) tissue sections containing cells derived from the same cells at the same positions on plane coordinates in the sections, and (2) tissue ns in which at least 50% or more, preferably 60% or more, more preferably 70% or more, further preferably 80% or more, still further preferably 90% or more, particularly preferably 95% or more of the cells are present at the same positions on the plane coordinates.

The heat-induced e val appropriately employs, for example, a heating method using microwave, a heating method using an autoclave, or a heating method using boiling treatment. In the case of boiling treatment at an output of 780 W so as to keep a liquid temperature at approximately 98°C, the time ed for the retrieval including the treatment is appropriately selected from between 5 minutes and 60 minutes and is, for example, 10 minutes. The epitope retrieval treatment can be performed in a 10 mM sodium e buffer solution as well as commercially available Target Retrieval Solution (DakoCytomation), for example. Target Retrieval Solution is used in Examples described below.

Any buffer solution or aqueous solution is preferably used as long as an epitope in the antigen that is recognized by an anti-GPC3 antibody acquires the ability to bind to the antibody as a result of the retrieval treatment so that an n-antibody complex mentioned later can be detected.

The protease for use in the protease-induced epitope retrieval is not limited by its type or origin.

Generally available protease can be riately selected for use. Preferred examples of the protease used include pepsin with 0.05% concentration in 0.01 N hloric acid, trypsin with 0.1% concentration further containing CaCl2 with 0.01% tration in a tris buffer on (pH 7.6), and protease K with a concentration of 1 to 50 µg/ml in a 10 mM tris-HCl buffer solution (pH 7.8) containing 10 mM EDTA and 0.5% SDS. In the case of using protease K, the pH of the reaction solution is appropriately selected from between 6.5 and 9.5, and an SH reagent, a trypsin inhibitor, or a chymotrypsin inhibitor may be appropriately used.

Specific examples of such preferred protease also include protease attached to Histofine HER2 kit (MONO) rei Biosciences Inc.). The protease ed epitope retrieval is usually performed at 37°C. The reaction temperature may be appropriately changed within the range of 25°C to 50°C. The reaction time of the proteaseinduced epitope retrieval performed at 37°C is appropriately selected from between, for example, 1 minute and 5 hours and is, for example, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 3 hours, or 4 hours.

After the completion of the val treatment, the tissue preparation thus treated is washed with a washing buffer solution. Phosphate-buffered saline (PBS) is preferably used as the washing buffer solution.

Alternatively, a tris-HCl buffer solution may be preferably used. The washing conditions adopted in this method usually involve three runs of washing at room temperature for 5 minutes. The washing time and temperature may be appropriately changed.

Reaction between tissue preparation and anti-GPC3 The tissue preparation thus treated by the heatinduced e retrieval and/or the tissue preparation thus treated by the protease-induced epitope retrieval are d with an anti-GPC3 antibody mentioned later as a primary antibody. The reaction is carried out under conditions appropriate for the recognition of an epitope in the antigen by the anti-GPC3 antibody and the subsequent ion of an antigen-antibody complex. The reaction is y carried out overnight at 4°C or at 37°C for 1 hour. The reaction conditions may be appropriately changed within a range appropriate for the ition of an e in the antigen by the antibody and the subsequent formation of an antigen-antibody complex. For example, the reaction ature may be changed within the range of 4°C to 50°C, while the reaction time may be changed between 1 minute and 7 days.

A longer reaction time is more preferred for the reaction carried out at a low temperature. After the completion of the primary dy reaction, each tissue preparation is washed with a washing buffer solution. Phosphatebuffered saline (PBS) is preferably used as the washing buffer solution. Alternatively, a tris-HCl buffer solution may be preferably used. The g conditions adopted in this method usually involve three runs of washing at room temperature for 5 minutes. The washing time and ature may be appropriately changed.

Subsequently, each tissue preparation thus reacted with the primary antibody is reacted with a secondary antibody that recognizes the primary dy. A secondary antibody d in advance with a labeling material for visualizing the secondary antibody is usually used. Preferred examples of the labeling material include: fluorescent dyes such as fluorescein isothiocyanate (FITC), Cy2 (Amersham Biosciences Corp.), and Alexa 488 ular Probes Inc.); enzymes such as dase and alkaline phosphatase; and gold colloid.

The reaction with the ary antibody is carried out under conditions appropriate for the formation of an antigen-antibody complex between the anti-GPC3 antibody and the ary antibody that recognizes the anti-GPC3 antibody. The on is usually carried out at room temperature or 37°C for 30 minutes to 1 hour. The reaction conditions may be appropriately changed within a range appropriate for the formation of an antigenantibody complex between the anti-GPC3 antibody and the secondary antibody. For example, the reaction temperature may be changed within the range of 4°C to 50°C, while the reaction time may be changed n 1 minute and 7 days. A longer reaction time is more preferred for the on carried out at a low temperature. After the completion of the secondary antibody reaction, each tissue ation is washed with a washing buffer on. Phosphate-buffered saline (PBS) is preferably used as the washing buffer solution.

Alternatively, a tris-HCl buffer solution may be preferably used. The washing conditions adopted in this method usually involve three runs of washing at room temperature for 5 minutes. The washing time and temperature may be riately changed.

Next, each tissue preparation thus reacted with the secondary antibody is reacted with a substance capable of visualizing the labeling material. When peroxidase is used as the labeling material in the ary antibody, a 0.02% aqueous hydrogen peroxide solution and a diaminobenzidine (DAB) solution concentration-adjusted to 0.1% with a 0.1 M tris-HCl buffer on (pH 7.2) are mixed in equal amounts immediately before incubation and the tissue preparation is incubated in the resulting reaction solution. A chromogenic ate such as DABNi or AEC+ (both from Dako Japan Inc.) may be riately selected d of DAB. During the course of incubation, the visualization reaction can be stopped by the dipping of the tissue preparation in PBS at the stage where appropriate color development is confirmed by the occasional microscopic observation of the degree of color development.

When alkaline phosphatase is used as the labeling material in the secondary antibody, each tissue preparation is incubated in a 5-bromochloroindolyl phosphoric acid (BCIP)/nitro blue tetrazolium (NBT) (Zymed Laboratories, Inc.) substrate solution (solution of NBT and BCIP dissolved at concentrations of 0.4 mM and 0.38 mM, tively, in a 50 mM sodium carbonate buffer solution (pH 9.8) containing 10 mM MgCl2 and 28 mM NaCl).

Alternatively, for e, Permanent Red, Fast Red, or Fuchsin+ (all from Dako Japan Inc.) may be appropriately used instead of BCIP and NBT. Prior to the incubation, the tissue preparation may be preincubated at room temperature for 1 minute to several hours with a 0.1 M tris-HCl buffer solution (pH 9.5) containing levamisole chloride ai Tesque, Inc.), an inhibitor of endogenous alkaline phosphatase, with a concentration of 1 mM, 0.1 M sodium chloride, and 50 mM ium chloride.

During the course of incubation, the tissue preparation is washed with water or with TBST (TBS containing 0.1% Tween 20) after stop of the reaction by the on of TBS containing 2% polyvinyl alcohol, at the stage where the deposition of a final reaction product purple formazan is confirmed by occasional microscopic observation. When gold colloid is used as the label in the secondary antibody, metallic silver is attached to gold particles by silver intensification to thereby visualize the gold colloid. The silver intensification method is lly known to those skilled in the art.

When a fluorescent dye such as fluorescein isothiocyanate (FITC), Cy2 (Amersham Biosciences , or Alexa 488 (Molecular Probes Inc.) is used as the ng material in the secondary antibody, the reaction step of the izing substance is unnecessary. Each tissue preparation is irradiated with light at an excitation wavelength for the fluorescent material.

Emitted light can be appropriately detected using a fluorescence microscope. histochemical staining score In a non-limiting aspect, the present invention also provides a method for determining the efficacy of GPC3- targeting drug therapy or determining the continuation of GPC3-targeting drug therapy from the concentration of free GPC3 as well as the expression level of GPC3 detected in s by the method described above. In a non-limiting aspect, the expression of GPC3 detected in tissues by the method described above is digitized by, for example, a miting method exemplified below. In the present invention, such a digitized expression level of GPC3 in tissues is ed to as an "immunohistochemical staining score of GPC3".

The tive scores of positive cell rate (PR), staining intensity of cytoplasm (SI-cp) or staining intensity of cell membrane (SI-cm), and staining pattern of cell membrane (Sp-cm) are calculated according to the criteria shown in Table 1 by a method described in 116659 and added on the basis of calculation expressions 1 and 2. The resulting score is exemplified as the non-limiting immunohistochemical staining score of GPC3 (referred to as "composite score 1" for the sake of convenience) of the present invention.

[Table 1-1] Criterion Evaluation Score Positive cell rate (PR) 0 0 1% or more and less than 20% 1 % or more and less than 50% 2 50% or more 3 Staining intensity (SI) ly positive 0 - Cytoplasm (SI-cp) Weakly positive 1 - Cell ne (SI-cm) Moderately positive and/or weakly positive 2 with strong positivity Moderately positive 3 Strongly positive 4 Staining pattern of cell Negative 0 membrane (SP-cm) When only a portion of the cell nes 1 of cells was stained When a portion of the cell membranes of 2 most of these cells was stained and the cell membranes of some of the cells were circumferentially stained When the cell membranes of most of these 3 cells were circumferentially stained (Sp-cm scores were calculated by the evaluation of cell staining in the visual field under microscope using an ive lens with a magnification of 4 or 10.) [Expression 1] [Expression 2] [Table 1-2] Composite score 1 IHC total score High expression 7 or higher Low or moderate expression Lower than 7 In addition, the H-score is known (literature: KS.

McCarty Jr. et al., Use of a monoclonal anti-Estrogen receptor antibody in the immunohistochemical evaluation of human tumors. Cancer Res. Suppl. (1986) 46, 4244s- 4248s), which is calculated on the basis of the tion of cells that exhibit each staining intensity (staining intensity of cell membrane or cytoplasm) classified into 0 to 3.

Another example of the histochemical staining score includes the following scoring algorithm for fication of 0 to 3+ on the basis of the staining intensity of membrane, the staining intensity of cytoplasm, and the degree of staining, and an tion score based on the algorithm (composite score 2).

[Table 2] Score Evaluation 0 When cell membranes were not d When less than 10% of tumor cells exhibited intracytoplasmic staining 1+ When less than 10% of tumor cells exhibited cell membrane staining and/or When 10% or more of tumor cells exhibited intracytoplasmic ng (note that strong intracytoplasmic staining, if any, remains at less than 50% of the tumor cells) 2+ When 10% or more of tumor cells exhibited weak or moderate cell membrane staining (note that strong cell membrane staining, if any, remains at less than 10% of the tumor cells) regardless of the presence or e of intracytoplasmic staining in 10% or more of the tumor cells (note that intracytoplasmic staining, if any, remains at less than 50% of the tumor cells) 3+ When 10% or more of tumor cells exhibited strong cell ne ng regardless of the presence or absence of intracytoplasmic staining When 50% or more of tumor cells exhibited strong intracytoplasmic staining In the present invention, for example, the composite score 1, the H-score, and the composite score 2 may be used alone or in ation as the "immunohistochemical staining score of GPC3". In a non -limiting aspect, the composite score 1 may be used as the "immunohistochemical staining score of GPC3". In another non -limiting aspect, the composite score 2 may be used as the "immunohistochemical staining score of GPC3".

GPC3-targeting drug In the present invention, the term "GPC3-targeting drug" refers to every molecule that blocks, suppresses, inhibits, or reduces the ical activity of GPC3 including a signal pathway mediated by GPC3 or is cytotoxic to cells expressing GPC3. The term "targeting ent" does not suggest a certain mechanism having biological effects and tually includes every possible effect of the pharmacological, physiological, and biochemical interactions of GPC3. Examples of the GPC3-targeting drug e: (1) antagonistic or nonantagonistic inhibitors of the binding of GPC3 to a GPC3- binding ligand, i.e., active substances that interfere with the binding of GPC3 to its ligand; (2) active substances that do not ere with the binding of GPC3 to its ligand but instead inhibit or decrease activity brought about by the binding of GPC3 to its ligand; (3) active substances that decrease GPC3 expression; and (4) active substances capable of eliciting cytotoxic activity against cells expressing GPC3. In a non -limiting aspect, examples of the ligand can include wnt (Cancer Res. (2005) 65, 6245-6254), IGF-II (Carcinogenesis (2008) 29 (7), 326), and fibroblast growth factor 2 (Int. J.

Cancer (2003) 103 (4), 455-465). In a non -limiting , such active substances can include, for example, antibodies ding their antigen-binding domains), nucleic acid molecules (antisense or RNAi molecules, etc.), peptides, non-peptidic low-molecular-weight organic materials.

In a non-limiting aspect, es of the nonpeptidic low-molecular-weight organic material that may be used as the GPC3-targeting drug of the present invention include non-peptidic lecular-weight quinoline derivatives (WO2008/046085) which act on methylation suppressor genes. Further examples thereof can include HLA-A2-restricted GPC3 peptide 144-152 (SEQ ID NO: 2) and HLA-A24-restricted GPC3 peptide 298-306 (SEQ ID NO: 3) (Clin. Cancer Res. (2006) 12 (9), 2689- 2697) which elicit the cytotoxic activity of cytotoxic T cells.

Anti-GPC3 dy In a non-limiting aspect, examples of the anti-GPC3 dy that may be used as the GPC3-targeting drug of the present invention can e an antibody-drug conjugate (ADC) (WO2007/137170) comprising a 1G12 antibody (WO2003/100429) (sold under catalog No. B0134R by BioMosaics Inc.) conjugated with a cytotoxic substance.

In an alternative miting aspect, examples of the anti-GPC3 antibody include a humanized anti-GPC3 antibody described in WO2006/006693 or WO2009/041062.

Specifically, a humanized anti-GPC3 antibody comprising heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 4, 5, and 6, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 ented by SEQ ID NOs: 7, 8, and 9, respectively, can be used as the argeting drug of the present invention. The humanized anti-GPC3 antibody can be prepared using, as tes for humanization, appropriately selected human framework ces having high sequence identity to a heavy chain framework sequence represented by SEQ ID NO: 10 or a light chain framework sequence represented by SEQ ID NO: 11.

In a further alternative non-limiting aspect, an anti-GPC3 chimeric antibody or a humanized anti-GPC3 antibody comprising heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 ented by SEQ ID NOs: 12, 13, and 14, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 15, 16, and 17, respectively, can be used as the GPC3- targeting drug of the present invention. The humanized anti-GPC3 antibody can be prepared using, as templates for humanization, riately selected human framework sequences having high sequence identity to a heavy chain framework sequence represented by SEQ ID NO: 18 or a light chain framework sequence represented by SEQ ID NO: In an alternative non-limiting aspect, an anti-GPC3 chimeric antibody or a humanized anti-GPC3 antibody comprising heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 20, 21, and 22, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 23, 24, and , respectively, can be used as the GPC3-targeting drug of the t invention. The humanized anti-GPC3 antibody can be prepared using, as templates for humanization, appropriately selected human framework sequences having high sequence ty to a heavy chain framework sequence represented by SEQ ID NO: 26 or a light chain ork sequence represented by SEQ ID NO: In a further alternative non-limiting aspect, an PC3 chimeric antibody or a humanized anti-GPC3 antibody comprising heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 28, 29, and 30, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 31, 32, and 33, respectively, can be used as the GPC3- targeting drug of the present invention. The humanized anti-GPC3 antibody can be prepared using, as templates for humanization, riately selected human framework sequences having high sequence identity to a heavy chain framework sequence represented by SEQ ID NO: 34 or a light chain framework sequence represented by SEQ ID NO: In an alternative non-limiting aspect, an anti-GPC3 chimeric antibody or a humanized anti-GPC3 antibody comprising heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 represented by SEQ ID NOs: 36, 37, and 38, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 represented by SEQ ID NOs: 39, 40, and 41, tively, can be used as the GPC3-targeting drug of the t invention. The humanized anti-GPC3 antibody can be prepared using, as templates for humanization, appropriately ed human framework sequences having high sequence identity to a heavy chain framework sequence represented by SEQ ID NO: 42 or a light chain framework sequence represented by SEQ ID NO: In a further alternative non-limiting aspect, a humanized anti-GPC3 dy sing a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region represented by SEQ ID NO: 51 can be used as the GPC3- targeting drug of the present invention. In a further alternative non-limiting aspect, a humanized anti-GPC3 antibody comprising a heavy chain variable region selected from the group of heavy chain variable regions represented by SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region selected from the group of light chain variable regions represented by SEQ ID NOs: 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, and 66 can be used as the GPC3-targeting drug of the present invention.

In a further alternative non-limiting aspect, a humanized anti-GPC3 antibody comprising a heavy chain variable region represented by SEQ ID NO: 67 and a light chain variable region represented by SEQ ID NO: 68, a humanized anti-GPC3 antibody comprising a heavy chain variable region ented by SEQ ID NO: 69 and a light chain variable region represented by SEQ ID NO: 70, a humanized anti-GPC3 antibody comprising a heavy chain variable region ented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 72, or a humanized PC3 antibody comprising a heavy chain variable region represented by SEQ ID NO: 71 and a light chain variable region represented by SEQ ID NO: 73 can also be used as the GPC3-targeting drug of the present invention. xic activity Alternative es of the anti-GPC3 antibody of the present invention include an PC3 antibody having cytotoxic activity. In the present ion, non-limiting examples of the xic activity include antibody-dependent cell-mediated cytotoxicity or antibody-dependent cellular cytotoxicity (ADCC) activity, complement-dependent cytotoxicity (CDC) activity, and cytotoxic activity based on T cells. In the t invention, the CDC activity means cytotoxic activity brought about by the complement system. On the ot her hand, the ADCC activity means the activity of damaging target cells by, for example, immunocytes, through the binding of the immunocytes via Fcγ receptors expressed on the immunocytes to the Fc regions of antigen-binding molecules comprising antigen-binding domains capable of binding to membrane molecules expressed on the cell membranes of the target cells. Whether or not the n-binding molecule of st has ADCC activity or has CDC ty can be determined by a method known in the art (e.g., Current protocols in Immunology, Chapter 7.

Immunologic studies in humans, Coligan et al., ed. (1993)).

Specifically, effector cells, a complement solution, and target cells are first prepared. (1) Preparation of effector cells The spleens are excised from CBA/N mice or the like, and spleen cells are separated therefrom in an 40 medium (Invitrogen Corp.). The spleen cells can be washed with this medium containing 10% fetal bovine serum (FBS, HyClone Laboratories, Inc.) and then concentrationadjusted to 5 × 106 mL to prepare the effector cells. (2) Preparation of complement solution Baby Rabbit Complement (CEDARLANE Laboratories Ltd.) can be diluted 10-fold with a medium (Invitrogen Corp.) containing 10% FBS to prepare the complement solution. (3) Preparation of target cells Antigen-expressing cells can be cultured at 37°C for 1 hour, together with 0.2 mCi 51Cr-sodium te (GE care Bio-Sciences Corp.), in a DMEM medium containing 10% FBS to y radiolabel the target cells.

The cells thus radiolabeled can be washed three times with an RPMI1640 medium containing 10% FBS and then concentration-adjusted to 2 × 105 cells/mL to prepare the target cells.

The ADCC or CDC activity can be assayed by a method described below. For the ADCC activity assay, the target cells and the antigen-binding molecule (each 50 l) are added to a U-bottom 96-well plate (Becton, Dickinson and Company) and reacted for 15 minutes on ice. Then, 100 µl of the effector cells is added to each well, and the plate is left standing for 4 hours in a CO2 incubator.

The final concentration of the antibody (antigen-binding molecule) can be set to, for example, 0 or 10 µg/ml. The radioactivity of 100 µl of the supernatant recovered from each well of the plate thus left standing is measured using a gamma counter (COBRA II AMMA, MODEL D5005, Packard Instrument Company). The cytotoxic activity (%) can be calculated on the basis of the calculation expression (A - C) / (B - C) × 100 using the measurement value, wherein A represents radioactivity (cpm) from each sample; B represents radioactivity (cpm) from a sample supplemented with 1% NP-40 (Nacalai Tesque, Inc.); and C represents radioactivity (cpm) from a sample containing only the target cells.

For the CDC activity assay, the target cells and the antigen-binding molecule (each 50 µl/well) are added to a flat-bottomed 96-well plate (Becton, Dickinson and Company) and reacted for 15 minutes on ice. Then, 100 µl of the ment solution is added to each well, and the plate is left standing for 4 hours in a CO2 tor.

The final concentration of the dy (antigen-binding molecule) can be set to, for example, 0 or 3 µg/ml. The radioactivity of 100 µl of the supernatant red from each well of the plate thus left standing is measured using a gamma counter. The cytotoxic activity based on the CDC activity can be calculated in the same way as in the ADCC activity assay.

Cytotoxic substance In a non-limiting aspect, alternative examples of the anti-GPC3 antibody of the t invention include an anti-GPC3 antibody conjugated with a cytotoxic substance. Such an anti-GPC3 antibody-drug conjugate (ADC) is specifically disclosed in, for example, WO2007/137170, though the conjugate of the t invention is not limited to those described therein.

Specifically, the cytotoxic substance may be any of chemotherapeutic agents listed below or may be a compound disclosed in Alley et al. (Curr. Opin. Chem. Biol. (2010) 14, 529-537) or WO2009/140242. Antigen -binding les are conjugated with these compounds via appropriate linkers or the like. es of chemotherapeutic agents that may be ated to the anti-GPC3 antibody of the present invention can include the following: azaribine, anastrozole, azacytidine, bleomycin, bortezomib, bryostatin-1, busulfan, camptothecin, 10- ycamptothecin, carmustine, Celebrex, chlorambucil, cisplatin, irinotecan, carboplatin, cladribine, cyclophosphamide, cytarabine, dacarbazine, docetaxel, dactinomycin, daunomycin glucuronide, daunorubicin, dexamethasone, lstilbestrol, doxorubicin, doxorubicin glucuronide, epirubicin, ethinyl estradiol, estramustine, etoposide, etoposide glucuronide, floxuridine, fludarabine, flutamide, uracil, fluoxymesterone, gemcitabine, hydroxyprogesterone caproate, hydroxyurea, idarubicin, ifosfamide, leucovorin, lomustine, maytansinoid, mechlorethamine, medroxyprogesterone acetate, megestrol acetate, melphalan, mercaptopurine, methotrexate, mitoxantrone, mithramycin, mitomycin, mitotane, phenylbutyrate, prednisone, bazine, paclitaxel, pentostatin, semustine, ozocin, tamoxifen, taxanes, Taxol, testosterone propionate, thalidomide, thioguanine, pa, teniposide, topotecan, uracil mustard, vinblastine, vinorelbine, and vincristine.

In the present invention, a preferred chemotherapeutic agent is a low-molecular-weight chemotherapeutic agent. The low-molecular-weight chemotherapeutic agent is unlikely to interfere with the functions of the PC3 antibody even after forming the anti-GPC3 antibody-drug conjugate of the present invention. In the present invention, the lecularweight chemotherapeutic agent has a lar weight of usually 100 to 2000, preferably 200 to 1000. All of the herapeutic agents listed herein are low-molecularweight chemotherapeutic agents. These chemotherapeutic agents according to the present invention include prodrugs that are converted to active chemotherapeutic agents in vivo. The prodrugs may be activated through enzymatic conversion or nonenzymatic conversion.

Alternative examples of the conjugated cytotoxic substance in the anti-GPC3 antibody-drug conjugate of the present invention can include toxic peptides (toxins) such as Pseudomonas exotoxin A, saporin-s6, diphtheria toxin, and cnidarian toxin, radioiodine, and photosensitizers. Examples of the toxic peptides preferably include the following: eria toxin A chain (Langone et al., s in Enzymology (1983) 93, 307-308); Pseudomonas exotoxin (Nature Medicine (1996) 2, 3); ricin A chain (Fulton et al., J. Biol. Chem. (1986) 261, 5314-5319; Sivam et al., Cancer Res. (1987) 47, 3169- 3173; Cumber et al., J. Immunol. Methods (1990) 135, 15- 24; Wawrzynczak et al., Cancer Res. (1990) 50, 7519-7562; and Gheeite et al., J. Immunol. Methods (1991) 142, 223- 230); deglycosylated ricin A chain e et al., Cancer Res. (1987) 47, 5924-5931); abrin A chain (Wawrzynczak et al., Br. J. Cancer (1992) 66, 361-366; Wawrzynczak et al., Cancer Res. (1990) 50, 7519-7562; Sivam et al., Cancer Res. (1987) 47, 3169- 3173; and Thorpe et al., Cancer Res. (1987) 47, 5924- 5931); gelonin (Sivam et al., Cancer Res. (1987) 47, 3169-3173; Cumber et al., J. Immunol. Methods (1990) 135, 15-24; Wawrzynczak et al., Cancer Res., (1990) 50, 7519-7562; and Bolognesi et al., Clin. exp. Immunol. (1992) 89, 341- 346); pokeweed anti-viral protein from seeds (PAP-s) (Bolognesi et al., Clin. exp. l. (1992) 89, 341-346); bryodin (Bolognesi et al., Clin. exp. Immunol. (1992) 89, 341-346); saporin (Bolognesi et al., Clin. exp. Immunol. (1992) 89, 341-346); momordin (Cumber et al., J. Immunol. s (1990) 135, -24; Wawrzynczak et al., Cancer Res. (1990) 50, 7519- 7562; and Bolognesi et al., Clin. exp. Immunol. (1992) 89, 341-346); momorcochin (Bolognesi et al., Clin. exp. l. (1992) 89, 341-346); dianthin 32 (Bolognesi et al., Clin. exp. Immunol. (1992) 89, 341-346); dianthin 30 (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); modeccin (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); viscumin e F., Barbieri L., FEBS letter (1986) 195, 1-8); volkensin (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); dodecandrin (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); tritin (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); luffin (Stirpe F., Barbieri L., FEBS letter (1986) 195, 1-8); and kirin (Casellas et al., Eur. J. Biochem. (1988) 176, 581-588; and Bolognesi et al., Clin. exp. Immunol., (1992) 89, 341-346).

In the case of ng the cytotoxic activity of the anti-GPC3 dy-drug conjugate of the present invention, the target cells and the PC3 antibodydrug conjugate (each 50 µl/well) are added to a flatbottomed 96-well plate (Becton, Dickinson and Company) and reacted for 15 minutes on ice. The plate is incubated for 1 to 4 hours in a CO2 incubator. The anti- GPC3 antibody-drug conjugate can be appropriately used at a final concentration ranging from 0 to 3 µg/ml. After the culture, 100 µl of the supernatant is recovered from each well, and the radioactivity of the supernatant is measured using a gamma counter. The xic activity can be calculated in the same way as in the ADCC activity assay.

Fc region An Fc region ned in a constant region contained in the anti-GPC3 antibody of the present invention may be obtained from human IgG, though the Fc region of the t invention is not d by a particular subclass of IgG. The Fc region refers to an antibody heavy chain constant region comprising a hinge region and CH2 and CH3 domains from the hinge region N terminus which is a papain cleavage site (about amino acid 216 based on the EU numbering). Preferred examples of the Fc region include Fc regions having binding activity against Fcγ receptors as mentioned later. In a non-limiting aspect, examples of such Fc regions include Fc regions contained in constant regions represented by SEQ ID NO: 74 for human IgG1, SEQ ID NO: 75 for IgG2, SEQ ID NO: 76 for IgG3, and SEQ ID NO: 77 for IgG4.

Fcγ receptor (FcγR) The Fcγ receptor (also referred to as FcγR) refers to a receptor capable of binding to the Fc region of an IgG1, IgG2, IgG3, or IgG4 monoclonal antibody and substantially means even any member of protein family encoded by Fcγ receptor genes. In humans, this family includes, but not limited to: FcγRI (CD64) ing isoforms FcγRIa, FcγRIb, and FcγRIc; FcγRII (CD32) including isoforms FcγRIIa (including allotypes H131 and R131; i.e., FcγRIIa (H) and a (R)), b (including FcγRIIb-1 and FcγRIIb-2), and FcγRIIc; FcγRIII (CD16) including isoforms FcγRIIIa (including allotypes V158 and F158; i.e., FcγRIIIa (V) and FcγRIIIa (F)) and FcγRIIIb (including allotypes Ib-NA1 and FcγRIIIb- NA2); and even any d human FcγR or FcγR isoform or allotype. FcγR includes human, mouse, rat, rabbit, and monkey Fcγ receptors. The FcγR of the present invention is not limited to these ors and may be derived from any organism. The mouse FcγR includes, but not limited to, FcγRI (CD64), FcγRII (CD32), FcγRIII (CD16), and FcγRIII-2 (FcγRIV, CD16-2), and even any unfound mouse FcγR or FcγR isoform or allotype. Preferred examples of such Fcγ receptors include human FcγRI , FcγRIIa , FcγRIIb (CD32), FcγRIIIa (CD16), and/or FcγRIIIb (CD16). The ptide sequence of human FcγRI is described in SEQ ID NO: 78 (NP_000557.1); the polypeptide sequence of human FcγRIIa (allotype H131) is described in SEQ ID NO: 79 (AAH20823.1) (allotype R131 has a sequence with substitution by Arg at amino acid 166 in SEQ ID NO: 79); the polypeptide sequence of FcγRIIb is described in SEQ ID NO: 80 (AAI46679.1); the polypeptide sequence of FcγRIIIa is described in SEQ ID NO: 81 (AAH33678.1); and the polypeptide sequence of FcγRIIIb is described in SEQ ID NO: 82 (AAI28563.1) (registration numbers of a database such as RefSeq are shown within the parentheses).

Whether or not the Fcγ receptor has g activity against the Fc region of an IgG1, IgG2, IgG3, or IgG4 monoclonal dy can be confirmed by a method known in the art such as FACS or ELISA formats as well as BIACORE method using amplified luminescent proximity neous assay (ALPHA) screening or surface n resonance (SPR) phenomena (Proc. Natl. Acad. Sci. U.S.A. (2006) 103 (11), 010).

In FcγRI (CD64) including isoforms FcγRIa, FcγRIb, and FcγRIc and FcγRIII (CD16) including isoforms FcγRIIIa (including allotypes V158 and F158) and FcγRIIIb (including allotypes FcγRIIIb-NA1 and FcγRIIIb-NA2), an α chain capable of binding to the IgG Fc region associates with a common γ chain having ITAM that transduces activating signals into cells. On the other hand, FcγRII (CD32) including isoforms FcγRIIa (including allotypes H131 and R131) and c contains ITAM in its cytoplasmic domain. These receptors are expressed in many immunocytes, such as macrophages, mast cells, and antigen-displaying cells. These ors bind to IgG Fc regions and thereby transduce activating signals, which in turn promote the phagocytic capacity of hages, the production of matory cytokines, the degranulation of mast cells, and the increased function of antigen-displaying cells. The Fcγ receptors that are able to transduce activating signals as described above are referred to as active Fcγ receptors herein.

On the other hand, FcγRIIb (including FcγRIIb-1 and FcγRIIb-2) contains ITIM that transduces inhibitory signals, in its intracytoplasmic domain. In B cells, ting signals from B cell receptors (BCRs) are ted by the cross-linking of BCR with FcγRIIb, resulting in the suppressed antibody production of BCR.

The phagocytic capacity of macrophages or their ability to produce inflammatory cytokines is suppressed by the linking of FcγRIII and FcγRIIb. The Fcγ receptors that are able to transduce inhibitory signals as described above are referred to as tory Fcγ receptors herein.

Binding activity of Fc region against FcγR As mentioned above, examples of the Fc region contained in the anti-GPC3 antibody of the present invention include Fc regions having g activity against Fcγ receptors. In a non-limiting aspect, es of such Fc regions include Fc regions contained in constant s represented by SEQ ID NO: 74 for human IgG1, SEQ ID NO: 75 for IgG2, SEQ ID NO: 76 for IgG3, and SEQ ID NO: 77 for IgG4. Whether or not the Fcγ receptor has binding activity t the Fc region of an IgG1, IgG2, IgG3, or IgG4 monoclonal antibody can be confirmed by a method known in the art such as FACS or ELISA formats as well as BIACORE method using amplified luminescent proximity homogeneous assay (ALPHA) screening or surface plasmon resonance (SPR) phenomena (Proc. Natl.

Acad. Sci. U.S.A. (2006) 103 (11), 4005-4010).

The ALPHA screening is carried out on the basis of the following principles according to ALPHA logy using two beads, a donor and an acceptor. Luminescence signals are ed only when these two beads are located in ity through the biological interaction between a molecule bound with the donor bead and a molecule bound with the acceptor bead. A excited ensitizer in the donor bead converts ambient oxygen to singlet oxygen in an excited state. The singlet oxygen diffuses around the donor bead and reaches the acceptor bead located in proximity thereto to thereby cause chemiluminescent reaction in the bead, which finally emits light. In the absence of the interaction between the molecule bound with the donor bead and the le bound with the acceptor bead, singlet oxygen produced by the donor bead does not reach the acceptor bead. Thus, no chemiluminescent reaction occurs.

For example, a biotin-labeled anti-GPC3 antibody comprising the Fc region is bound to the donor bead, while a glutathione S transferase (GST)-tagged Fcγ receptor is bound to the acceptor bead. In the e of a competing anti-GPC3 antibody comprising a modified Fc region, the anti-GPC3 antibody having the native Fc region interacts with the Fcγ receptor to te signals of 520 to 620 nm. An anti -GPC3 dy comprising an untagged modified Fc region competes with the PC3 antibody having the native Fc region for the interaction with the Fcγ receptor. Decrease in fluorescence caused as a result of the competition can be quantified to thereby determine relative binding affinity.

The antibody biotinylation using sulfo-NHS-biotin or the like is known in the art. The Fcγ receptor can be tagged with GST by an appropriately adopted method which involves, for example: fusing a polynucleotide encoding the Fcγ receptor in flame with a polynucleotide encoding GST; operably ligating the resulting fusion gene with a vector; and allowing cells or the like carrying the vector to s the gged Fcγ receptor, which is then purified using a hione column. The obtained signals are preferably analyzed using, for example, software GRAPHPAD PRISM (GraphPad Software, Inc., San Diego) adapted to a one-site competition model based on ear regression analysis.

One (ligand) of the substances between which the interaction is to be observed is immobilized on a thin gold film of a sensor chip. The sensor chip is irradiated with light from the back such that total reflection occurs at the interface between the thin gold film and glass. As a result, a site having a drop in reflection intensity (SPR signal) is formed in a portion of reflected light. The other (analyte) of the substances between which the interaction is to be observed is flowed on the surface of the sensor chip and bound to the ligand so that the mass of the immobilized ligand molecule is increased to change the tive index of the solvent on the sensor chip surface. This change in the refractive index shifts the on of the SPR signal (on the contrary, the iation of the bound molecules gets the signal back to the original position). The Biacore system plots on the te the amount of the shift, i.e., change in mass on the sensor chip surface, and displays time-dependent change in mass as assay data (sensorgram). Kinetics: an association rate constant (ka) and a dissociation rate constant (kd) can be determined from the curve of the sensorgram, and affinity (KD) can be determined from the ratio between these constants. Inhibition assay is also preferably used in the BIACORE method. Examples of the inhibition assay are described in Lazor et al. (Proc. Natl. Acad.

Sci. U.S.A. (2006) 103 (11), 010).

Fcγ receptor (FcγR)-binding modified Fc region In addition to the Fc regions contained in constant regions represented by SEQ ID NO: 74 for human IgG1, SEQ ID NO: 75 for IgG2, SEQ ID NO: 76 for IgG3, and SEQ ID NO: 77 for IgG4, an FcγR-binding modified Fc region having higher binding activity against Fcγ receptors than that of the Fc region of native human IgG against Fcγ receptors may be appropriately used as the Fc region contained in the PC3 antibody of the present invention. The "Fc region of native human IgG" described herein means an Fc region having a fucose-containing sugar chain as a sugar chain bound to on 297 (EU ing) of the Fc region contained in the human IgG1, IgG2, IgG3, or IgG4 constant region represented by SEQ ID NO: 74, 75, 76, or 77. Such an FcγR-binding modified Fc region can be prepared by the amino acid modification of the native human IgG Fc region. Whether or not the FcγR- binding modified Fc region has higher binding activity against FcγR than that of the native human IgG Fc region t FcγR can be appropriately confirmed by a method known in the art such as FACS or ELISA formats as well as BIACORE method using ied luminescent proximity homogeneous assay (ALPHA) screening or surface plasmon resonance (SPR) phenomena as described above.

In the present invention, the ication of amino acid(s)" or "amino acid modification" of the Fc region includes modification to an amino acid sequence different from the amino acid sequence of the starting Fc region.

Any Fc region can be used as the starting Fc region as long as the modified form of the starting Fc region can bind to the human Fcγ receptor in a neutral region of pH.

Alternatively, an Fc region further modified from an already modified Fc region as the starting Fc region may be preferably used as the Fc region of the present invention. The ng Fc region may mean the polypeptide , a composition containing the starting Fc region, or an amino acid sequence ng the starting Fc region. The starting Fc region can include Fc regions known in the art produced by recombination reviewed in the paragraph about the antibody. The starting Fc region is not limited by its origin and can be obtained from an arbitrary nonhuman animal organism or a human. Preferred examples of the arbitrary organism include an organism selected from mice, rats, guinea pigs, hamsters, gerbils, cats, rabbits, dog, goats, sheep, cattle, horses, camels, and nonhuman primates. In another aspect, the starting Fc region may be obtained from a lgus monkey, a et, a rhesus monkey, a chimpanzee, or a human. Preferably, the starting Fc region can be obtained from human IgG1, though the starting Fc region of the present invention is not d by a particular class of IgG. This means that the Fc region of human IgG1, IgG2, IgG3, or IgG4 can be appropriately used as the ng Fc region. Likewise, this means herein that the Fc region of arbitrary IgG class or subclass from the arbitrary organism can be preferably used as the starting Fc region. Examples of variants of lly occurring IgG or manipulated forms thereof are described in literatures known in the art (Curr. Opin. Biotechnol. (2009) 20 (6), 685-91; Curr.

Opin. Immunol. (2008) 20 (4), 460-470; Protein Eng. Des.

Sel. (2010) 23 (4), 195-202; and International Publication Nos. WO2009/086320, /092117, WO2007/041635, and WO2006/105338), though the variants or the manipulated forms of the t invention are not limited to those described therein.

Examples of the cation include one or more variations, for example, a variation that substitutes amino acid(s) in the starting Fc region by amino acid residue(s) different therefrom, the insertion of one or more amino acid residues into the amino acid sequence of the starting Fc region, and/or the deletion of one or more amino acids from the amino acid sequence of the starting Fc . Preferably, the amino acid sequence of the Fc region thus modified comprises an amino acid sequence containing at least a nonnatural portion of the Fc region. Such a variant inevitably has less than 100% sequence identity or similarity to the starting Fc region.

In a preferred embodiment, the variant has an amino acid ce with imately 75% to less than 100% sequence identity or similarity, more preferably approximately 80% to less than 100%, further preferably approximately 85% to less than 100%, still r preferably approximately 90% to less than 100%, most preferably approximately 95% to less than 100% sequence identity or similarity to the amino acid sequence of the starting Fc region. In a non-limiting aspect of the present invention, the starting Fc region and the FcγR- binding modified Fc region of the present invention differ by at least one amino acid. The difference in amino acid between the ng Fc region and the FcγR- binding ed Fc region of the present ion may be ably determined by a difference in amino acid with the identified position of its amino acid residue defined particularly by the EU numbering.

The amino acid(s) in the Fc region can be modified by an appropriately adopted method known in the art such as site-directed mutagenesis (Kunkel et al., Proc. Natl.

Acad. Sci. USA (1985) 82, 488-492) or overlap extension PCR. Also, a plurality of methods known in the art can be adopted as methods for modifying an amino acid to substitute the amino acid by an amino acid other than natural one (Annu. Rev. Biophys. Biomol. Struct. (2006) , 225-249; and Proc. Natl. Acad. Sci. U.S.A. (2003) 100 (11), 357). For exa mple, a tRNA-containing cellfree translation system (Clover Direct (Protein Express, an R & D oriented y)) comprising a non-natural amino acid bound with an amber suppressor tRNA complementary to UAG codon (amber codon), which is a stop codon, is also preferably used.

The FcγR-binding modified Fc region (contained in the antigen-binding molecule of the present invention) having higher binding activity against Fcγ receptors than that of the native human IgG Fc region t Fcγ receptors can be obtained by any method. Specifically, the FcγR-binding modified Fc region can be obtained by the amino acid modification of a human IgG globulin Fc region used as the starting Fc region. Examples of the IgG immunoglobulin Fc region preferred for the cation include Fc regions contained in human IgG (IgG1, IgG2, IgG3, and IgG4, and ed forms thereof) constant regions represented by SEQ ID NOs: 74, 75, 76, and 77.

The modification to other amino acids can e amino acid modification at any position as long as the resulting Fc region has higher binding activity against Fcγ receptors than that of the native human IgG Fc region against Fcγ receptors. When the antigen-binding molecule contains a human IgG1 Fc region as a human Fc region, the modification preferably allows the Fc region to contain a -containing sugar chain as a sugar chain bound to position 297 (EU numbering) and is effective for producing higher binding activity against Fcγ receptors than that of the native human IgG Fc region against Fcγ receptors. Such amino acid modification has been reported in, for e, International Publication Nos.

WO2007/024249, WO2007/021841, WO2006/031370, /042072, WO2004/029207, WO2004/099249, WO2006/105338, WO2007/041635, WO2008/092117, WO2005/070963, WO2006/020114, WO2006/116260, and WO2006/023403.

Examples of amino acids that may undergo such modification include at least one or more amino acids selected from the group consisting of position 221, position 222, position 223, position 224, position 225, position 227, position 228, position 230, position 231, position 232, position 233, position 234, on 235, position 236, position 237, position 238, position 239, on 240, position 241, position 243, position 244, position 245, position 246, position 247, on 249, position 250, position 251, position 254, position 255, position 256, position 258, position 260, position 262, position 263, position 264, position 265, position 266, position 267, position 268, position 269, position 270, position 271, position 272, position 273, position 274, position 275, position 276, position 278, on 279, position 280, position 281, position 282, position 283, position 284, position 285, position 286, position 288, on 290, position 291, position 292, position 293, position 294, position 295, position 296, position 297, position 298, position 299, position 300, position 301, position 302, position 303, position 304, position 305, position 311, position 313, on 315, position 317, position 318, position 320, position 322, position 323, position 324, position 325, position 326, position 327, position 328, position 329, position 330, position 331, position 332, position 333, position 334, position 335, position 336, position 337, position 339, position 376, position 377, position 378, on 379, position 380, on 382, position 385, position 392, position 396, position 421, position 427, position 428, position 429, position 434, position 436 and position 440 based on the EU ing. The modification of these amino acids can yield the Fc region (FcγR-binding ed Fc region) having higher binding activity t Fcγ receptors than that of the native human IgG Fc region against Fcγ receptors.

Examples of particularly preferred modification for use in the present invention include at least one or more amino acid modifications selected from the group consisting of modifications of amino acid 221 to Lys or Tyr, amino acid 222 to Phe, Trp, Glu, or Tyr, amino acid 223 to Phe, Trp, Glu, or Lys, amino acid 224 to Phe, Trp, Glu, or Tyr, amino acid 225 to Glu, Lys, or Trp, amino acid 227 to Glu, Gly, Lys, or Tyr, amino acid 228 to Glu, Gly, Lys, or Tyr, amino acid 230 to Ala, Glu, Gly, or Tyr, amino acid 231 to Glu, Gly, Lys, Pro, or Tyr, amino acid 232 to Glu, Gly, Lys, or Tyr, amino acid 233 to Ala, Asp, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 234 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 235 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 236 to Ala, Asp, Glu, Phe, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 237 to Asp, Glu, Phe, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 238 to Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 239 to Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Thr, Val, Trp, or Tyr, amino acid 240 to Ala, Ile, Met, or Thr, amino acid 241 to Asp, Glu, Leu, Arg, Trp, or Tyr, amino acid 243 to Leu, Glu, Leu, Gln, Arg, Trp, or Tyr, amino acid 244 to His, amino acid 245 to Ala, amino acid 246 to Asp, Glu, His, or Tyr, amino acid 247 to Ala, Phe, Gly, His, Ile, Leu, Met, Thr, Val, or Tyr, amino acid 249 to Glu, His, Gln, or Tyr, amino acid 250 to Glu, or Gln, amino acid 251 to Phe, amino acid 254 to Phe, Met, or Tyr, amino acid 255 to Glu, Leu, or Tyr, amino acid 256 to Ala, Met, or Pro, amino acid 258 to Asp, Glu, His, Ser, or Tyr, amino acid 260 to Asp, Glu, His, or Tyr, amino acid 262 to Ala, Glu, Phe, Ile, or Thr, amino acid 263 to Ala, Ile, Met, or Thr, amino acid 264 to Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Trp, or Tyr, amino acid 265 to Ala, Leu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 266 to Ala, Ile, Met, or Thr, amino acid 267 to Asp, Glu, Phe, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Thr, Val, Trp, or Tyr, amino acid 268 to Asp, Glu, Phe, Gly, Ile, Lys, Leu, Met, Pro, Gln, Arg, Thr, Val, or Trp, amino acid 269 to Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 270 to Glu, Phe, Gly, His, Ile, Leu, Met, Pro, Gln, Arg, Ser, Thr, Trp, or Tyr, amino acid 271 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 272 to Asp, Phe, Gly, His, Ile, Lys, Leu, Met, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 273 to Phe, or Ile, amino acid 274 to Asp, Glu, Phe, Gly, His, Ile, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 275 to Leu, or Trp, amino acid 276 to Asp, Glu, Phe, Gly, His, Ile, Leu, Met, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 278 to Asp, Glu, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, or Trp, amino acid 279 to Ala, amino acid 280 to Ala, Gly, His, Lys, Leu, Pro, Gln, Trp, or Tyr, amino acid 281 to Asp, Lys, Pro, or Tyr, amino acid 282 to Glu, Gly, Lys, Pro, or Tyr, amino acid 283 to Ala, Gly, His, Ile, Lys, Leu, Met, Pro, Arg, or Tyr, amino acid 284 to Asp, Glu, Leu, Asn, Thr, or Tyr, amino acid 285 to Asp, Glu, Lys, Gln, Trp, or Tyr, amino acid 286 to Glu, Gly, Pro, or Tyr, amino acid 288 to Asn, Asp, Glu, or Tyr, amino acid 290 to Asp, Gly, His, Leu, Asn, Ser, Thr, Trp, or Tyr, amino acid 291 to Asp, Glu, Gly, His, Ile, Gln, or Thr, amino acid 292 to Ala, Asp, Glu, Pro, Thr, or Tyr, amino acid 293 to Phe, Gly, His, Ile, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 294 to Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 295 to Asp, Glu, Phe, Gly, His, Ile, Lys, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 296 to Ala, Asp, Glu, Gly, His, Ile, Lys, Leu, Met, Asn, Gln, Arg, Ser, Thr, or Val, amino acid 297 to Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 298 to Ala, Asp, Glu, Phe, His, Ile, Lys, Met, Asn, Gln, Arg, Thr, Val, Trp, or Tyr, amino acid 299 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Val, Trp, or Tyr, amino acid 300 to Ala, Asp, Glu, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, or Trp, amino acid 301 to Asp, Glu, His, or Tyr, amino acid 302 to Ile, amino acid 303 to Asp, Gly, or Tyr, amino acid 304 to Asp, His, Leu, Asn, or Thr, amino acid 305 to Glu, Ile, Thr, or Tyr, amino acid 311 to Ala, Asp, Asn, Thr, Val, or Tyr, amino acid 313 to Phe, amino acid 315 to Leu, amino acid 317 to Glu or Gln, amino acid 318 to His, Leu, Asn, Pro, Gln, Arg, Thr, Val, or Tyr, amino acid 320 to Asp, Phe, Gly, His, Ile, Leu, Asn, Pro, Ser, Thr, Val, Trp, or Tyr, amino acid 322 to Ala, Asp, Phe, Gly, His, Ile, Pro, Ser, Thr, Val, Trp, or Tyr, amino acid 323 to Ile, amino acid 324 to Asp, Phe, Gly, His, Ile, Leu, Met, Pro, Arg, Thr, Val, Trp, or Tyr, amino acid 325 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 326 to Ala, Asp, Glu, Gly, Ile, Leu, Met, Asn, Pro, Gln, Ser, Thr, Val, Trp, or Tyr, amino acid 327 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Arg, Thr, Val, Trp, or Tyr, amino acid 328 to Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 329 to Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 330 to Cys, Glu, Phe, Gly, His, Ile, Lys, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 331 to Asp, Phe, His, Ile, Leu, Met, Gln, Arg, Thr, Val, Trp, or Tyr, amino acid 332 to Ala, Asp, Glu, Phe, Gly, His, Lys, Leu, Met, Asn, Pro, Gln, Arg, Ser, Thr, Val, Trp, or Tyr, amino acid 333 to Ala, Asp, Glu, Phe, Gly, His, Ile, Leu, Met, Pro, Ser, Thr, Val, or Tyr, amino acid 334 to Ala, Glu, Phe, Ile, Leu, Pro, or Thr, amino acid 335 to Asp, Phe, Gly, His, Ile, Leu, Met, Asn, Pro, Arg, Ser, Val, Trp, or Tyr, amino acid 336 to Glu, Lys, or Tyr, amino acid 337 to Glu, His, or Asn, amino acid 339 to Asp, Phe, Gly, Ile, Lys, Met, Asn, Gln, Arg, Ser, or Thr, amino acid 376 to Ala, or Val, amino acid 377 to Gly, or Lys, amino acid 378 to Asp, amino acid 379 to Asn, amino acid 380 to Ala, Asn, or Ser, amino acid 382 to Ala, or Ile, amino acid 385 to Glu, amino acid 392 to Thr, amino acid 396 to Leu, amino acid 421 to Lys, amino acid 427 to Asn, amino acid 428 to Phe, or Leu, amino acid 429 to Met, amino acid 434 to Trp, amino acid 436 to Ile, or amino acid 440 to Gly, His, Ile, Leu, or Tyr based on the EU numbering in the Fc region. The number of amino acids to be modified is not limited. Only one amino acid may be modified, or two or more amino acids may be modified. Examples of combinations of amino acid modifications at two or more positions e combinations as described in Table 3 s 3-1 to 3-3).

Also, WO2007/047291 discloses specific examples of the anti-GPC3 antibody comprising the FcγR-binding modified Fc region having higher binding activity against Fcγ receptors than that of the native human IgG Fc region against Fcγ receptors.

[Table 3-1] ation of amino acids Combination of amino acids [Table 3-2] [Table 3-3] The Fcγ receptor-binding domain contained in the anti-GPC3 antibody of the present invention can be assayed for its binding activity against the Fcγ receptor riately using pH conditions selected from acidic to neutral regions of pH. The acidic to neutral regions of pH as the conditions under which the Fcγ receptor-binding domain contained in the antigen-binding molecule of the present invention is d for its binding activity against the Fcγ receptor usually mean pH 5.8 to pH 8.0.

The pH range is preferably indicated by arbitrary pH values from pH 6.0 to pH 7.4 and is preferably selected from pH 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, and 7.4. ularly, a pH range of 6.15 to 7.4, which is close to the pH of cancer tissues, is preferred (Vaupel et al., Cancer Res. (1989) 49, 6449- 6665). The bindin g affinity of the Fc region for the human Fcγ receptor can be evaluated under assay conditions involving an arbitrary temperature of 10°C to 50°C. Preferably, a temperature of 15°C to 40°C is used for determining the binding affinity of the Fc region for the human Fcγ receptor. More preferably, an arbitrary temperature of 20°C to 35°C, for example, any one temperature of 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, and 35°C, is also used for ining the binding ty of the Fc region for the Fcγ receptor. The temperature 25°C is one non-limiting example in an aspect of the present ion.

The phrase "FcγR-binding modified Fc region having higher binding activity against Fcγ receptors than that of the native Fc region against Fcγ receptors" described herein means that the inding modified Fc region has higher binding activity against any of the human Fcγ receptors FcγRI, FcγRIIa, FcγRIIb, FcγRIIIa, and /or FcγRIIIb than that of the native Fc region t the human Fcγ receptor. The phrase means that, for example, on the basis of the analysis method described above, the anti-GPC3 antibody comprising the FcγR-binding ed Fc region exhibits 105% or more, preferably 110% or more, 115% or more, 120% or more, or 125% or more, particularly preferably 130% or more, 135% or more, 140% or more, 145% or more, 150% or more, 155% or more, 160% or more, 165% or more, 170% or more, 175% or more, 180% or more, 185% or more, 190% or more, 195% or more, 2 times or more, 2.5 times or more, 3 times or more, 3.5 times or more, 4 times or more, 4.5 times or more, 5 times or more, 7.5 times or more, 10 times or more, 20 times or more, 30 times or more, 40 times or more, 50 times or more, 60 times or more, 70 times or more, 80 times or more, 90 times or more, 100 times or more binding activity compared with the binding activity of an anti-GPC3 antibody comprising the native Fc region of human IgG serving as a control. The native Fc region used may be the ng Fc region or may be the native Fc region of an antibody of the same subclass as the anti-GPC antibody concerned.

In the present invention, a native human IgG Fc region having a fucose-containing sugar chain as a sugar chain bound to amino acid 297 (EU numbering) is preferably used as the native Fc region of human IgG serving as a control. Whether or not the sugar chain bound to amino acid 297 (EU ing) is a fucosecontaining sugar chain can be confirmed using an approach known in the art. Whether or not the sugar chain bound to the native human IgG Fc region is a fucose-containing sugar chain can be determined by, for example, a method as shown below. The native human IgG to be tested liberates a sugar chain through reaction with NGlycosidase F (Roche Diagnostics K.K.) (Weitzhandler et al., J. Pharma. Sciences (1994) 83, 12, 1670-1675). Next, proteins are removed through reaction with ethanol, and the resulting reaction solution (Schenk et al., J. Clin. igation (2001) 108 (11) 1687-1695) is evaporated to dryness and then fluorescently labeled with 2- aminobenzamide (Bigge et al., Anal. Biochem. (1995) 230 (2) 229-238). After removal of the reagent by solid - phase tion using a cellulose cartridge, the 2-AB- fluorescently labeled sugar chain is analyzed by normalphase chromatography. The detected peak in the chromatogram can be observed to y determine whether or not the sugar chain bound to the native Fc region of human IgG is a -containing sugar chain.

An anti-GPC3 antibody having an IgG onal antibody Fc region can be appropriately used as the anti- GPC3 antibody comprising the native Fc region of an antibody of the same subclass serving as a control.

Structural es of the Fc region include Fc regions contained in constant regions represented by SEQ ID NOs: 74 (having A added to the N terminus of the sequence of database registration No. AAC82527.1), 75 (having A added to the N us of the sequence of database registration No. AAB59393.1), 76 (database registration No. CAA27268.1), and 77 (having A added to the N terminus of the sequence of se registration No. AAB59394.1).

In the case of using a certain isotype of anti-GPC3 antibody as a test substance, the anti-GPC3 dy comprising the Fc region to be tested is studied for its effect of g activity against Fcγ receptors by use of an anti-GPC3 antibody of the certain isotype as a control. The anti-GPC3 antibody comprising the Fc region thus confirmed to have higher binding activity against Fcγ receptors is riately selected.

Fc region having higher binding activity against active Fcγ receptor than its binding activity against inhibitory Fcγ receptor As described above, preferred es of the active Fcγ receptors include FcγRI (CD64) including FcγRIa, FcγRIb, and , FcγRIIa, and FcγRIII (CD16) including isoforms FcγRIIIa (including allotypes V158 and F158) and Ib (including allotypes FcγRIIIb-NA1 and FcγRIIIb- NA2). Preferred examples of the inhibitory Fcγ receptors include FcγRIIb (including FcγRIIb-1 and FcγRIIb-2).

In a non-limiting aspect, ative examples of the anti-GPC3 antibody of the present invention include an anti-GPC3 antibody sing an Fc region having higher binding activity against active Fcγ receptors than its binding activity against inhibitory Fcγ receptors.

In this case, the phrase "having higher binding activity against active Fcγ receptors than its binding activity against inhibitory Fcγ receptors" means that the Fc region has higher binding activity against any of the human Fcγ receptors , FcγRIIa, FcγRIIIa, and/or FcγRIIIb than its binding ty against FcγRIIb. The phrase means that, for example, on the basis of the analysis method described above, the antigen-binding molecule comprising the Fc region exhibits 105% or more, preferably 110% or more, 120% or more, 130% or more, or 140% or more, particularly preferably 150% or more, 160% or more, 170% or more, 180% or more, 190% or more, 200% or more, 250% or more, 300% or more, 350% or more, 400% or more, 450% or more, 500% or more, 750% or more, 10 times or more, 20 times or more, 30 times or more, 40 times or more, 50 times, 60 times, 70 times, 80 times, 90 times, or 100 times or more binding ty against any of the human Fcγ receptors FcγRIa, a, FcγRIIIa, and/or Ib compared with its binding activity against FcγRIIb. The IgG dy comprising such an Fc region is known to have enhancement in the ADCC activity.

Thus, the anti-GPC3 antibody comprising the Fc region is useful as the GPC3-targeting drug of the present invention.

In a non-limiting aspect of the present invention, examples of the Fc region having higher binding activity against active Fcγ receptors than its binding activity against inhibitory Fcγ ors (having ive binding activity against active Fcγ receptors) preferably include Fc regions in which at least one or more amino acids selected from the group consisting of position 221, position 222, position 223, position 224, position 225, position 227, position 228, position 230, position 231, position 232, position 233, position 234, position 235, position 236, position 237, position 238, position 239, position 240, position 241, position 243, position 244, position 245, on 246, position 247, position 249, position 250, position 251, position 254, position 255, position 256, position 258, position 260, position 262, position 263, position 264, position 265, position 266, position 267, position 268, position 269, position 270, position 271, position 272, on 273, position 274, on 275, on 276, position 278, position 279, position 280, position 281, position 282, position 283, position 284, position 285, position 286, position 288, position 290, on 291, on 292, position 293, position 294, position 295, position 296, position 297, position 298, on 299, position 300, position 301, position 302, position 303, position 304, position 305, position 311, position 313, position 315, position 317, position 318, on 320, position 322, position 323, position 324, position 325, position 326, on 327, position 328, position 329, position 330, position 331, position 332, position 333, position 334, position 335, position 336, position 337, position 339, position 376, on 377, position 378, position 379, position 380, position 382, position 385, position 392, position 396, position 421, position 427, position 428, position 429, position 434, position 436 and position 440 (EU numbering) are modified to amino acids ent from those in the native Fc region.

In a non-limiting aspect of the present invention, further examples of the Fc region having higher binding activity against active Fcγ receptors than its binding activity against inhibitory Fcγ receptors (having selective binding activity against active Fcγ receptors) preferably include Fc regions in which a ity of amino acids described in Tables 3-1 to 3-3 are modified to amino acids different from those in the native Fc region.

Fc region having modified sugar chain The Fc region contained in the anti-GPC3 antibody provided by the t invention can also e an Fc region modified such that a higher proportion of fucosedeficient sugar chains is bound to the Fc region or a higher proportion of bisecting N-acetylglucosamine is added to the Fc region in the composition of sugar chains bound to the Fc region. The removal of a fucose residue from N-acetylglucosamine at the reducing end of a N- glycoside-linked complex sugar chain bound to an dy Fc region is known to enhance its affinity for FcγRIIIa (Sato et al., Expert Opin. Biol. Ther. (2006) 6 (11), 1161-1173). An IgG1 antibody comprising such an Fc region is known to have enhancement in the ADCC activity.

Thus, the antigen-binding le comprising the Fc region is also useful as the antigen-binding molecule contained in the pharmaceutical composition of the present invention. Examples of an antibody that lacks a fucose residue in N-acetylglucosamine at the reducing end of a N-glycoside-linked complex sugar chain bound to the antibody Fc region include the following antibodies: glycosylated antibodies (e.g., International ation No. WO1999/054342); and antibodies deficient in fucose added to the sugar chain (e.g., International ation Nos. WO2000/061739, WO2002/031140, and WO2006/067913).

Also, WO2006/046751 and WO2009/ 041062 disclose ic examples of the anti-GPC3 dy comprising the Fc region modified such that a higher tion of fucosedeficient sugar chains is bound to the Fc region or a higher proportion of bisecting N-acetylglucosamine is added to the Fc region in the composition of sugar chains bound to the Fc region.

More specifically, in an alternative non-limiting aspect of the antibody that lacks a fucose residue in N- acetylglucosamine at the reducing end of a N-glycosidelinked complex sugar chain bound to the antibody Fc region, the antibody deficient in fucose added to the sugar chain (e.g., ational Publication Nos.

WO2000/061739, WO2002/031140, and WO2006/067913) may be prepared. For this purpose, host cells less able to add fucose to sugar chains are prepared as a result of altering the activity of forming the sugar chain structures of polypeptides that undergo sugar chain modification. The host cells are allowed to express the desired antibody gene, and the antibody deficient in fucose in its sugar chain can be recovered from the culture solution of the host cells. Non-limiting preferred examples of the activity of forming the sugar chain structures of polypeptides can include the ty of an enzyme or a transporter selected from the group consisting of fucosyltransferase (EC 2.4.1.152), fucose transporter (SLC35C1), GDP-mannose 4,6-dehydratase (GMD) (EC 4.2.1.47), GDP-ketodeoxymannose imerase/4- reductase (Fx) (EC 1.1.1.271), and GDP-β-L-fucose osphorylase (GFPP) (EC 2.7.7.30). These enzymes or orters are not necessarily limited by their structures as long as the enzymes or the transporters can exert their activity. These proteins capable of exerting such activity are referred to as functional proteins herein. In a non-limiting aspect, examples of methods for altering the activity include the deletion of the activity. Host cells that lack the ty can be prepared by an appropriately adopted method known in the art such as a method which involves disrupting the genes of these onal proteins to render the genes unfunctional (e.g., International Publication Nos.

WO2000/061739, WO2002/031140, and WO2006/067913). Such host cells that lack the activity may be prepared by, for example, a method which involves ting the endogenous genes of these functional proteins in cells such as CHO cells, BHK cells, NS0 cells, SP2/0 cells, YO myeloma cells, P3X63 mouse myeloma cells, PER cells, PER.C6 cells, HEK293 cells, or hybridoma cells to render the genes unfunctional.

Antibodies containing sugar chains having bisecting GlcNAc (e.g., International Publication No.

WO2002/079255) are known in the art. In a non-limiting aspect, host cells expressing genes encoding functional proteins having β-1,4-mannosyl-glycoprotein 4-β-N- acetylglucosaminyltransferase (GnTIII) (EC 2.4.1.144) activity or β-1,4-galactosyltransferase (GalT) (EC 2.4.1.38) activity are ed in order to prepare such an antibody containing sugar chains having bisecting GlcNAc. In another non -limiting preferred aspect, host cells coexpressing a gene encoding a onal protein having human mannosidase II (ManII) (3.2.1.114) activity, a gene encoding a functional protein having β-1,2- acetylglucosaminyltransferase I (GnTI) (EC 2.4.1.94) activity, a gene encoding a functional protein having β- 1,2-acetylglucosaminyltransferase II (GnTII) (EC 2.4.1.143) activity, a gene encoding a functional protein having mannosidase I (ManI) (EC 3.2.1.113) activity, and an α-1,6-fucosyltransferase (EC 2.4.1.68) gene, in addition to the functional proteins described above, are prepared (International Publication Nos. WO2004/065540).

The host cells less able to add fucose to sugar chains and the host cells having the activity of forming sugar chains having bisecting GlcNAc structures as described above can be ormed with antibody genecontaining expression vectors to respectively prepare the antibody that lacks a fucose residue in N- acetylglucosamine at the ng end of a osidelinked x sugar chain bound to the antibody Fc region and the antibody containing sugar chains having bisecting GlcNAc. The methods for producing these antibodies are also applicable to a method for producing the antigen-binding le sing the Fc region ed such that a higher proportion of fucosedeficient sugar chains is bound to the Fc region or a higher proportion of bisecting N-acetylglucosamine is added to the Fc region in the composition of sugar chains bound to the Fc region of the present invention. The composition of sugar chains bound to the Fc region contained in the antigen-binding molecule of the present ion prepared by such a tion method can be confirmed by the method described in the paragraph "Fcγ receptor (FcγR)-binding modified Fc region".

Anti-GPC3 antibody having altered ctric point In a miting aspect, further examples of the anti-GPC3 antibody that may be used in the present invention include an anti-GPC3 antibody having an amino acid residue modified to alter its isoelectric point (pI).

Preferred examples of the "alteration of the electric charge of an amino acid residue" in the anti-GPC3 antibody provided by the present invention are as follows: alteration to increase the pI value can be performed by, for example, at least one substitution selected from the substitution of Q by K at position 43, the substitution of D by N at position 52, and the substitution of Q by R at position 105 based on the Kabat numbering in the anti-GPC3 antibody heavy chain variable region represented by SEQ ID NO: 50, which is consequently modified to, for example, the amino acid sequence represented by SEQ ID NO: 67. Also, this tion can be performed by, for example, at least one substitution selected from the substitution of E by Q at on 17, the substitution of Q by R at position 27, and the tution of Q by R at position 105 based on the Kabat numbering in the anti-GPC3 antibody light chain variable region represented by SEQ ID NO: 51 or 66, which is consequently modified to, for example, the amino acid sequence represented by SEQ ID NO: 68. On the other hand, alteration to decrease the pI value can be performed by at least one substitution selected from the substitution of K by T at on 19, the substitution of Q by E at position 43, the substitution of G by E at position 61, the tution of K by S at position 62, the substitution of K by Q at position 64, and the substitution of G by D at position 65 based on the Kabat numbering in the anti-GPC3 antibody heavy chain variable region represented by SEQ ID NO: 50, which is consequently modified to, for example, the amino acid sequence represented by SEQ ID NO: 69 or 71. Also, this alteration can be performed by, for example, at least one tution selected from the substitution of R by Q at position 24, the substitution of Q by E at position 27, the substitution of K by T at position 74, the substitution of R by S at position 77, and the substitution of K by E at position 107 based on the Kabat numbering in the anti-GPC3 antibody light chain variable region represented by SEQ ID NO: 51 or 66, which is consequently modified to, for example, the amino acid sequence ented by SEQ ID NO: 70, 72, or 73.

Further examples of the alteration to decrease the pI value include the substitution of at least one amino acid selected from amino acids 268, 274, 355, 356, 358, and 419 based on the EU numbering in the heavy chain constant region represented by SEQ ID NO: 74. Preferred examples of these substitutions can include at least one substitution selected from the substitution of H by Q at position 268, the tution of K by Q at position 274, the substitution of R by Q at position 355, the substitution of D by E at on 356, the substitution of L by M at position 358, and the substitution of Q by E at position 419 based on the EU numbering in the heavy chain constant region represented by SEQ ID NO: 31. As a result of these substitutions, a chimera having human antibody IgG1 and IgG4 constant regions is constructed. ically, these substitutions can yield an antibody having the desired pI without influencing the immunogenicity of the modified antibody. cation to reduce heterogeneity An IgG constant region deficient in Gly at on 446 and Lys at position 447 based on the EU numbering in the IgG constant region represented by SEQ ID NO: 74, 75, 76, or 77 may also be used as the constant region contained in the anti-GPC3 antibody of the present invention. Deficiency in both of these amino acids can reduce heterogeneity derived from the end of the heavy chain nt region of the antibody.

Antibody modification The posttranslational modification of a polypeptide refers to chemical modification given to the ptide ated during polypeptide biosynthesis. Since the y structure of an dy is composed of a polypeptide, the anti-GPC3 antibody of the present invention also includes a modified form that has received the posttranslational modification of the polypeptide constituting the primary structure of the anti-GPC3 antibody. The posttranslational modification of a polypeptide can be broadly classified into the addition of a functional group, the addition of a polypeptide or a peptide (ISGylation, SUMOylation, or tination), the conversion of the chemical properties of an amino acid (silylation, deamination, or deamidation), and structural conversion (disulfidation or protease ation). In a non-limiting aspect, examples of the posttranslational modification according to the present invention include the addition of a peptide or a onal group to an amino acid residue as a unit constituting the polypeptide.

Examples of such modification can ically include phosphorylation (serine, threonine, tyrosine, aspartic acid, etc.), glucosylation (serine, threonine, aspartic acid, etc.), acylation (lysine), acetylation (lysine), hydroxylation (lysine and proline), prenylation ine), palmitoylation (cysteine), alkylation (lysine and arginine), polyglutamylation (glutamic acid), carboxylation mic acid), polyglycylation (glutamic acid), citrullination (arginine), and succinimide formation (aspartic acid). For example, an anti-GPC3 antibody that has received the modification of N-terminal glutamine to pyroglutamic acid by pyroglutamylation is also included in the anti-GPC3 antibody of the present invention, as a matter of course. Also, for e, a posttranslationally modified anti-GPC3 antibody comprising heavy and light chains or heavy chains linked via a fide bond", which means a covalent bond formed between two sulfur atoms is included in the anti- GPC3 antibody of the present invention. A thiol group contained in an amino acid cysteine can form a disulfide bond or crosslink with a second thiol group. In general IgG molecules, CH1 and CL regions are linked via a disulfide bond, and two polypeptides constituting heavy chains are linked via a ide bond between cysteine residues at positions 226 and 229 based on the EU numbering. A posttranslationally ed anti-GPC3 antibody having such a linkage via a disulfide bond is also ed in the anti-GPC3 antibody of the present invention.

GPC3-targeting drug therapy The term "GPC3-targeting drug therapy" refers to the administration of a GPC3-targeting drug to a patient.

The phrase "efficacy of GPC3-targeting drug therapy for cancer" or "GPC3-targeting drug y has efficacy for cancer" means that the GPC3-targeting drug therapy produces desired or beneficial s on a patient diagnosed with cancer. The desired or beneficial effects can include: (1) the inhibition of the further growth or diffusion of cancer cells; (2) the killing of cancer cells; (3) the inhibition of cancer recurrence; (4) the alleviation, reduction, mitigation, or inhibition of cancer-related symptoms (pain, etc.) or ion in the frequency of the symptoms; and (5) improvement in the survival rate of the t. The inhibition of cancer recurrence includes the inhibition of the growth of cancer already treated by radiation, chemotherapy, surgical operation, or other techniques, at the primary site of the cancer and its neighboring tissues, and the absence of the growth of cancer at a new distal site.

The desired or beneficial effects may be subjectively perceived by the patient or may be objectively found. In the case of, for example, a human patient, the human is able to recognize improvement in energy or vitality or reduction in pain as improvement or a therapy-responsive sign perceived by the patient. Alternatively, a clinician is able to notice se in tumor size or the amount of tumor tissues on the basis of findings gained by physical ation, experimental parameters, tumor markers, or X-ray photography. Some experimental signs that can be observed by the clinician in response to treatment include normalized test results of, for example, leukocyte counts, erythrocyte counts, et counts, erythrocyte sedimentation rates, and levels of s enzymes. The clinician is further able to e decrease in detectable tumor marker level. Alternatively, other tests, such as sonography, nuclear magnetic resonance test, and positron emission test, may be used for evaluating objective improvement.

Any cancer having high expression of targeted GPC3 corresponds to the cancer to be treated by the GPC3- targeting drug therapy of the present invention. One example of such cancer include cancer selected from breast cancer, e cervix , colon cancer, uterine body cancer, head and neck cancer, liver cancer, lung cancer, malignant carcinoid, ant glioma, malignant lymphoma, malignant melanoma, ovary cancer, pancreatic cancer, prostatic cancer, renal , skin cancer, gastric cancer, testicle cancer, thyroid cancer, lial cancer, and the like.

Method for determining efficacy of GPC3-targeting drug y or method for determining continuation of GPC3- targeting drug therapy In a non-limiting aspect, the present invention provides a method comprising monitoring a concentration of free GPC3 in a biological sample isolated from a t before the start of GPC3-targeting drug therapy and/or a patient treated with GPC3-targeting drug therapy, wherein when the concentration of free GPC3 is a predetermined value, the efficacy of the argeting drug y is determined or the continuation of the therapy is determined. The "patient before the start of GPC3-targeting drug therapy" refers to a patient sed with cancer, having no history of administration of the GPC3-targeting drug. The patient may be a patient for which the efficacy of the GPC3- targeting drug therapy has been determined from the expression level of GPC3 in the tissues. Further, the "patient treated with GPC3-targeting drug therapy" refers to a patient having a history of administration of the GPC3-targeting drug. The administration route of the GPC3-targeting drug can be appropriately selected from stration routes suitable for the properties, etc., of the GPC3-targeting drug to be administered. es of the administration route e parenteral administration. Further examples of the parenteral administration include injection, transnasal administration, transpulmonary administration, and percutaneous administration. Further es of the injection include systemic or local administration based on intravenous injection, intramuscular injection, intraperitoneal injection, and subcutaneous injection.

Known results gained by conventional techniques before the completion of the present invention show that free GPC3 ed into plasma by sing at a particular site in the polypeptide sequence of GPC3 by an enzyme such as convertase, phospholipase D, or Notum is detected in plasma isolated from liver cancer patients, s free GPC3 is not detected in plasma isolated from healthy individuals (Patent Literature 7, etc.). It has been expected from such results that the concentration of free GPC3 detected in serum or plasma is sed over time with the continuation of the treatment, if the GPC3- targeting drug therapy has efficacy. As a result of conducting diligent studies under such circumstances, singly, the present inventors have found that the concentration of free GPC3 is stabilized or increased, rather than decreased, in serum or plasma isolated from a patient with stable disease that may respond to the GPC3- targeting drug therapy. The present inventors have also found that when the concentration of free GPC3 detected in serum or plasma before administration of GPC3- targeting drug therapy is equal to or higher than the predetermined concentration, the cy of the GPC3- targeting drug therapy is determined.

In a miting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in a biological sample isolated from the patient, wherein when the concentration is a predetermined value, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or ined or the continuation of the therapy is determined. The predetermined value may be determined from particular values such as 0.1 ng/mL, 0.2 ng/mL, 0.3 ng/mL, 0.4 ng/mL, 0.5 ng/mL, 0.6 ng/mL, 0.7 ng/mL, 0.8 ng/mL, 0.9 ng/mL, 1.0 ng/mL, 2.0 ng/mL, 3.0 ng/mL, 4.0 ng/mL, 5.0 ng/mL, 6.0 ng/mL, 7.0 ng/mL, 8.0 ng/mL, 9.0 ng/mL, 10.0 ng/mL, 15.0 ng/mL, 20.0 ng/mL, 25.0 ng/mL, .0 ng/mL, 35.0 ng/mL, 40.0 ng/mL, 45.0 ng/mL, 50.0 ng/mL, 55.0 ng/mL, 60.0 ng/mL, 65.0 ng/mL, 70.0 ng/mL, 75.0ng/mL, 80.0 ng/mL, 85.0 ng/mL, 90.0 ng/mL, 100.0 ng/mL or may be determined as a cal range containing particular values arbitrarily selected as the upper and lower limits from the above group of particular . As an example, such a numerical range can be appropriately selected from numerical ranges of 0.1 ng/mL to 100 ng/mL. Examples of the numeric range include 0.1 to 100 ng/mL, 0.5 to 80 ng/mL, 1.0 to 60 ng/mL, 2.0 to 55 ng/mL, 3.0 to 50 ng/mL, 4.0 to 45 ng/mL, 5.0 to 40 ng/mL, 6.0 to 35 ng/mL, 7.0 to 30 ng/mL, 8.0 to 25 ng/mL, 9.0 to ng/mL, and 10 to 20 ng/mL. The numerical range is, for example, preferably 0.1 to 0.35 ng/mL, more preferably 0.15 to 0.3 ng/mL, though the numerical range of the present invention is not limited to these ranges.

The predetermined value of the concentration of free GPC3 can slightly vary depending on many factors, for example, the assay method used, the type of a sample for free GPC3 assay, storage conditions (e.g., temperature and duration) of the sample, and the ethnic identity of the patient. In the method for predicting, expecting, or determining the efficacy or determining the continuation of the therapy, a concentration in a blood, plasma, or serum sample isolated from the patient is ed as the tration of free GPC3.

The tration of free GPC3 can be measured in a sample ed before and/or after the start of the GPC3-targeting drug therapy and may be measured in a plurality of samples collected at ermined time intervals. When the concentration of free GPC3 in any one of the plurality of samples collected at predetermined time intervals is the predetermined concentration, the efficacy of the argeting drug therapy for cancer in the patient is predicted, expected, or determined or the continuation of the therapy is determined. The predetermined time intervals are riately set. In a non-limiting aspect of the intervals, the samples can be collected at als of 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days (i.e., 1 week), 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days (i.e., 2 weeks), 15 days, 16 days, 17 days, 18 days, 19 days, 20 days, 21 days (i.e., 3 weeks), 22 days, 23 days, 24 days, 25 days, 26 days, 27 days, 28 days (i.e., 4 weeks), 29 days, 30 days, 1 month, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 2 months, 3 months, 4 months, 5 months, or 6 months after the initial administration of the GPC3-targeting drug, or at arbitrary points in time between the start and completion of the therapy, for example, after 1, 2, 3, 4 or more treatment cycles. The dosing intervals, i.e., the treatment cycles, can be appropriately set. One iting example thereof includes 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days (i.e., 1 week), 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days (i.e., 2 weeks), 15 days, 16 days, 17 days, 18 days, 19 days, 20 days, 21 days (i.e., 3 weeks), 22 days, 23 days, 24 days, days, 26 days, 27 days, 28 days (i.e., 4 weeks), 29 days, 30 days, 1 month, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 2 months, 3 months, 4 months, 5 months, or 6 months.

In a non-limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the t treated with the therapy, wherein when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the efficacy of the GPC3-targeting drug therapy is determined. In another non -limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, , or serum isolated 2 months, 3 months, 4 , 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient treated with the therapy, n when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the efficacy of the GPC3-targeting drug therapy is determined.

In a non-limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug y from the patient treated with the therapy, n when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the continuation of the GPC3-targeting drug therapy is determined. In another non-limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 , 4 months, 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the tration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the continuation of the GPC3-targeting drug therapy is determined.

In another non-limiting aspect of the present invention, the concentration of free GPC3 can be compared with a concentration of free GPC3 ("baseline concentration") measured in a blood, plasma, or serum sample isolated before the start of the GPC3-targeting drug therapy from the t. In this aspect, the "predetermined value" of the tration of free GPC3 means that the concentration of free GPC3 in the biological sample isolated from the patient treated with the argeting drug therapy is equal to or higher than the baseline concentration. Specifically, when the concentration of free GPC3 after the start of the GPC3- targeting drug therapy is equal to or larger than that before the start of the therapy in one patient, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or determined or the continuation of the y is determined. The rate at which the concentration of free GPC3 after the start of the GPC3-targeting drug therapy is equal to or larger than that before the start of the therapy can be appropriately selected by those skilled in the art and is not limited to a particular value. Such a rate can be appropriately selected from a cal range of 1 time to 106 times. When the rate is, for example, 1 time or more, 1.05 times or more, 1.1 times or more, 1.2 times or more, 1.3 times or more, 1.4 times or more, 1.5 times or more, 1.6 times or more, 1.7 times or more, 1.8 times or more, 1.9 times or more, 2 times or more, 2.1 times or more, 2.2 times or more, 2.3 times or more, 2.4 times or more, 2.5 times or more, 2.6 times or more, 2.7 times or more, 2.8 times or more, 2.9 times or more, 3 times or more, 3.1 times or more, 3.2 times or more, 3.3 times or more, 3.4 times or more, 3.5 times or more, 3.6 times or more, 3.7 times or more, 3.8 times or more, 3.9 times or more, 4 times or more, 4.1 times or more, 4.2 times or more, 4.3 times or more, 4.4 times or more, 4.5 times or more, 4.6 times or more, 4.7 times or more, 4.8 times or more, 4.9 times or more, 5 times or more, 5.1 times or more, 5.2 times or more, 5.3 times or more, 5.4 times or more, 5.5 times or more, 5.6 times or more, 5.7 times or more, 5.8 times or more, 5.9 times or more, 6 times or more, 6.1 times or more, 6.2 times or more, 6.3 times or more, 6.4 times or more, 6.5 times or more, 6.6 times or more, 6.7 times or more, 6.8 times or more, 6.9 times or more, 7 times or more, 7.1 times or more, 7.2 times or more, 7.3 times or more, 7.4 times or more, 7.5 times or more, 7.6 times or more, 7.7 times or more, 7.8 times or more, 7.9 times or more, 8 times or more, 8.1 times or more, 8.2 times or more, 8.3 times or more, 8.4 times or more, 8.5 times or more, 8.6 times or more, 8.7 times or more, 8.8 times or more, 8.9 times or more, 9 times or more, 9.1 times or more, 9.2 times or more, 9.3 times or more, 9.4 times or more, 9.5 times or more, 9.6 times or more, 9.7 times or more, 9.8 times or more, 9.9 times or more, 10 times or more, 11 times or more, 12 times or more, 13 times or more, 14 times or more, 15 times or more, 16 times or more, 17 times or more, 18 times or more, 19 times or more, 20 times or more, 21 times or more, 22 times or more, 23 times or more, 24 times or more, 25 times or more, 26 times or more, 27 times or more, 28 times or more, 29 times or more, 30 times or more, 31 times or more, 32 times or more, 33 times or more, 34 times or more, 35 times or more, 36 times or more, 37 times or more, 38 times or more, 39 times or more, 40 times or more, 41 times or more, 42 times or more, 43 times or more, 44 times or more, 45 times or more, 46 times or more, 47 times or more, 48 times or more, 49 times or more, 50 times or more, 55 times or more, 60 times or more, 65 times or more, 70 times or more, 75 times or more, 80 times or more, 85 times or more, 90 times or more, 95 times or more, 100 times or more, 105 times or more, 110 times or more, 120 times or more, 130 times or more, 140 times or more, 150 times or more, 160 times or more, 170 times or more, 180 times or more, 190 times or more, 200 times or more, 220 times or more, 240 times or more, 260 times or more, 280 times or more, 300 times or more, 320 times or more, 340 times or more, 360 times or more, 380 times or more, 400 times or more, 420 times or more, 440 times or more, 460 times or more, 480 times or more, 500 times or more, 550 times or more, 600 times or more, 650 times or more, 700 times or more, 750 times or more, 800 times or more, 850 times or more, 900 times or more, 950 times or more, 1000 times or more, 2000 times or more, 3000 times or more, 4000 times or more, 5000 times or more, 6000 times or more, 7000 times or more, 8000 times or more, 9000 times or more, 104 times or more, 2 × 104 times or more, 4 × 104 times or more, 6 × 104 times or more, 8 × 104 times or more, 105 times or more, 2 × 105 times or more, 4 × 105 times or more, 6 × 105 times or more, 8 × 105 times or more, or 106 times or more, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or ined or the continuation of the therapy is determined.

In a non-limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is equal to or larger than the ne concentration, the efficacy of the GPC3- targeting drug therapy is determined. In another non - limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 , or 6 months after the start of GPC3- targeting drug therapy from the patient d with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration, the efficacy of the GPC3-targeting drug therapy is determined.

As described above, when the concentration of free GPC3 is equal to or larger than the baseline tration, the efficacy of the GPC3-targeting drug therapy is determined. In this ure, the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer ), isolated from the t may be taken into consideration. Specifically, when the concentration of free GPC3 in the patient is equal to or larger than the baseline concentration and the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a particular evaluation score, the efficacy of the GPC3-targeting drug therapy is determined. In another non-limiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, , or serum isolated 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration and the expression level of GPC3 in a , particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score, the efficacy of the argeting drug therapy is determined.

In a miting aspect, examples of the case where the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score can include high expression and low or moderate expression (IHC total score: 7 or higher and lower than 7, tively) in a composite score calculated as a result of staining according to the staining method 1. In a miting , alternative examples of the case where the expression level of GPC3 is equal to or larger than a predetermined immunohistochemical staining score can e GPC3-IHC scores of 1+, 2+, and 3+ calculated as a result of staining according to the staining method In a non-limiting , the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is equal to or larger than the baseline concentration, the continuation of the GPC3- targeting drug therapy is determined. In another nonlimiting aspect, the method of the present invention comprises monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 , or 6 months after the start of GPC3- targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration, the continuation of the GPC3-targeting drug therapy is determined.

As described above, when the concentration of free GPC3 is equal to or larger than the ne tration, the uation of the GPC3-targeting drug therapy is determined. In this procedure, the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient may be taken into consideration.

Specifically, when the concentration of free GPC3 in the patient is equal to or larger than the baseline concentration and the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a ular evaluation score, the continuation of the argeting drug therapy is determined. In another non-limiting aspect, the method of the present invention ses monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3-targeting drug y from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration and the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score, the continuation of the argeting drug therapy is ined.

In a non-limiting aspect, examples of the case where the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score can include high expression and low or te expression (IHC total score: 7 or higher and lower than 7, respectively) in a composite score calculated as a result of staining according to the staining method 1. In a non-limiting aspect, alternative examples of the case where the expression level of GPC3 is equal to or larger than a predetermined immunohistochemical staining score can include GPC3-IHC scores of 1+, 2+, and 3+ calculated as a result of staining according to the staining method Drug and preparation In the present invention, the drug usually refers to an agent for the treatment or prevention of a disease or for examination or diagnosis. In the present invention, the phrase targeting drug which is to be administered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient before the start of GPC3-targeting drug therapy" may be ated into a "method for treating cancer, comprising administering a GPC3-targeting drug to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer t before the start of GPC3-targeting drug therapy" or may be translated into "use of a GPC3-targeting drug which is to be stered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient before the start of GPC3-targeting drug therapy, for production of an agent for the treatment of cancer". In the present invention, the phrase "GPC3-targeting drug which is to be further administered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of GPC3-targeting drug therapy" may be translated into a "method for treating , comprising further administering a GPC3-targeting drug to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of GPC3-targeting drug therapy" or may be translated into "use of a GPC3- ing drug which is to be further administered to a cancer patient having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of GPC3- targeting drug therapy, for production of an agent for the ent of cancer". The phrase "having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of argeting drug therapy" may be translated into the phrase "the concentration of free GPC3 in the biological sample isolated from the cancer patient after the start of GPC3-targeting drug y has been increased as a result of receiving the GPC3- targeting drug therapy".

The drug of the present invention can be formulated using a method generally known to those skilled in the art. For example, the drug of the present ion can be parenterally used in the form of an injection in a sterile on or suspension with water or any other pharmaceutically acceptable solution. For example, the active ingredient can be appropriately combined with pharmacologically acceptable rs or media, specifically, sterile water or saline, a plant oil, an emulsifier, a suspending agent, a surfactant, a stabilizer, a flavor, an excipient, a vehicle, an antiseptic, a binder, and the like and mixed ith in a unit dosage form required for generally accepted pharmaceutical practice to produce preparations. The amount of the active ingredient in these preparations is set to give an appropriate volume within a ibed range.

Sterile compositions for injection can be formulated according to usual pharmaceutical practice using a vehicle such as injectable distilled water. Examples of injectable aqueous solutions include saline and isotonic solutions containing glucose or other nts (e.g., D- sorbitol, D-mannose, D-mannitol, and sodium chloride).

An appropriate solubilizer, for example, an alcohol (ethanol, etc.), a polyalcohol (propylene glycol, polyethylene glycol, etc.), or a nonionic surfactant (Polysorbate 80(TM), HCO-50, etc.) may be used in combination therewith.

Examples of oil solutions include sesame oil and soybean oil. Benzyl benzoate and/or benzyl alcohol may be used as a solubilizer in combination therewith. These injectable solutions may be mixed with a buffer (e.g., a phosphate buffer solution and a sodium acetate buffer solution), a soothing agent (e.g., procaine hydrochloride), a stabilizer (e.g., benzyl alcohol and phenol), and an antioxidant. The prepared ions are y charged into appropriate ampules.

The drug of the present invention is preferably administered by eral administration. For example, the drug is administered in a dosage form of an injection, a transnasal agent, a transpulmonary agent, or a aneous agent. The drug can be administered systemically or locally by, for example, intravenous injection, intramuscular ion, intraperitoneal injection, or subcutaneous injection.

The stration method can be appropriately ed according to the age and ms of the patient.

The single dose of a pharmaceutical preparation containing the drug can be set within the range of, for example, 0.0001 mg to 1000 mg per kg body weight.

Alternatively, the dose can be set to, for example, 0.001 to 100000 mg per patient, though the dose of the present invention is not necessarily limited to these numeric values. The dose and the administration method vary depending on the body weight, age, symptoms, etc. of the patient. Those skilled in the art can set an appropriate dose and administration method in consideration of these ions. As a preferred example of the dose and the administration method of the present invention, the drug of the present invention can be administered to achieve a blood trough level equal to or higher than a predetermined level in the patient. Preferred examples of the blood trough level can include 150 µg/mL or higher, 160 µg/mL or higher, 170 µg/mL or higher, 180 µg/mL or higher, 190 µg/mL or higher, 200 µg/mL or higher, 210 µg/mL or higher, 220 µg/mL or higher, 230 µg/mL or higher, 240 µg/mL or , 250 µg/mL or higher, 260 µg/mL or higher, 270 µg/mL or higher, 280 µg/mL or higher, 290 µg/mL or higher, 300 µg/mL or higher, and 400 µg/mL or higher. More preferred examples thereof can include 200 µg/mL or higher.

The ation of the present invention comprises an ction stating that the preparation is to be further administered to a cancer t having a predetermined value of a concentration of free GPC3 in a biological sample isolated from the cancer patient after the start of GPC3-targeting drug y. In another non-limiting aspect, the preparation of the present invention comprises an instruction stating that the preparation is to be further administered to a cancer patient in which the concentration of free GPC3 in the biological sample isolated from the cancer patient after the start of GPC3-targeting drug therapy has been increased as a result of ing the GPC3-targeting drug therapy.

In a non-limiting aspect, the t invention provides the preparation comprising an instruction stating that the patient is selected on the basis of a method comprising ring a concentration of free GPC3 in a biological sample isolated from the patient treated with the GPC3-targeting drug therapy, wherein when the concentration of free GPC3 is a predetermined value, the efficacy of the GPC3-targeting drug therapy is determined or the continuation of the therapy is determined.

In a non-limiting aspect, the present invention provides the preparation comprising an instruction stating that the patient is selected on the basis of a method comprising ring a concentration of free GPC3 in a biological sample isolated from the patient, wherein when the concentration is a ermined value, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or determined or the continuation of the therapy is determined. The predetermined value may be determined from particular values such as 0.1 ng/mL, 0.2 ng/mL, 0.3 ng/mL, 0.4 ng/mL, 0.5 ng/mL, 0.6 ng/mL, 0.7 ng/mL, 0.8 ng/mL, 0.9 ng/mL, 1.0 ng/mL, 2.0 ng/mL, 3.0 ng/mL, 4.0 ng/mL, 5.0 ng/mL, 6.0 ng/mL, 7.0 ng/mL, 8.0 ng/mL, 9.0 ng/mL, 10.0 ng/mL, .0 ng/mL, 20.0 ng/mL, 25.0 ng/mL, 30.0 ng/mL, 35.0 ng/mL, 40.0 ng/mL, 45.0 ng/mL, 50.0 ng/mL, 55.0 ng/mL, 60.0 ng/mL, 65.0 ng/mL, 70.0 ng/mL, 75.0 ng/mL, 80.0 ng/mL, 85.0 ng/mL, /mL, 100.0 ng/mL or may be determined as a numerical range containing particular values arily selected as the upper and lower limits from the above group of particular values. As an example, such a numerical range can be appropriately selected from numerical ranges of 0.1 ng/mL to 100 ng/mL. Examples of the numeric range include 0.1 to 100 ng/mL, 0.5 to 80 ng/mL, 1.0 to 60 ng/mL, 2.0 to 55 ng/mL, 3.0 to 50 ng/mL, 4.0 to 45 ng/mL, 5.0 to 40 ng/mL, 6.0 to 35 ng/mL, 7.0 to ng/mL, 8.0 to 25 ng/mL, 9.0 to 20 ng/mL, and 10 to 20 ng/mL. The numerical range is, for example, preferably 0.1 to 0.35 ng/mL, more preferably 0.15 to 0.3 ng/mL, though the numerical range of the present invention is not limited to these . The predetermined value of the concentration of free GPC3 can slightly vary depending on many factors, for e, the assay method used, the type of a sample for free GPC3 assay, storage conditions (e.g., temperature and on) of the sample, and the ethnic identity of the patient. In the method for predicting, expecting, or ining the efficacy or determining the continuation of the therapy, a concentration in a blood, plasma, or serum sample ed from the patient is measured as the concentration of free GPC3.

The concentration of free GPC3 can be measured in a sample isolated before and/or after the start of the GPC3-targeting drug therapy and may be measured in a plurality of samples collected at predetermined time intervals. When the concentration of free GPC3 in any one of the plurality of s collected at predetermined time intervals is the predetermined concentration, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or determined or the continuation of the therapy is determined. The predetermined time intervals at which the sample is collected after the start of the GPC3- targeting drug therapy are appropriately set. In a non - limiting aspect of the intervals, the samples can be collected at intervals of 1 day, 2 days, 3 days, 4 days, days, 6 days, 7 days (i.e., 1 week), 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days (i.e., 2 weeks), days, 16 days, 17 days, 18 days, 19 days, 20 days, 21 days (i.e., 3 weeks), 22 days, 23 days, 24 days, 25 days, 26 days, 27 days, 28 days (i.e., 4 weeks), 29 days, 30 days, 1 month, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 2 months, 3 months, 4 months, 5 months, or 6 months after the initial administration of the GPC3- targeting drug, or at arbitrary points in time between the start and tion of the y, for example, after 1, 2, 3, 4 or more treatment cycles. The dosing intervals, i.e., the treatment cycles, can be appropriately set. One non-limiting example thereof includes 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days (i.e., 1 week), 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days (i.e., 2 weeks), 15 days, 16 days, 17 days, 18 days, 19 days, 20 days, 21 days (i.e., 3 weeks), 22 days, 23 days, 24 days, 25 days, 26 days, 27 days, 28 days (i.e., 4 weeks), 29 days, 30 days, 1 month, weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 2 months, 3 , 4 months, 5 , or 6 months.

In a non-limiting aspect, the instruction states that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the y, wherein when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the efficacy of the GPC3-targeting drug therapy is determined.

In another non-limiting aspect, the instruction states that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 , 3 months, 4 months, 5 months, or 6 months after the start of GPC3- targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the efficacy of the GPC3-targeting drug therapy is determined.

In a non-limiting aspect, the instruction states that the patient is selected on the basis of a method comprising ring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the tration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the continuation of the GPC3-targeting drug y is determined. In another miting aspect, the instruction states that the patient is selected on the basis of a method comprising monitoring a tration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 months, or 6 months after the start of argeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 ranges from 0.1 ng/mL to 100 ng/mL, the continuation of the GPC3-targeting drug therapy is determined.

In another non-limiting aspect of the present invention, the concentration of free GPC3 can be compared with a tration of free GPC3 ("baseline concentration") ed in a blood, plasma, or serum sample isolated before the start of the GPC3-targeting drug therapy from the patient. In this aspect, the termined value" of the concentration of free GPC3 means that the concentration of free GPC3 in the biological sample isolated from the patient treated with the GPC3-targeting drug therapy is equal to or higher than the baseline concentration. Specifically, when the concentration of free GPC3 after the start of the GPC3- targeting drug therapy is equal to or larger than that before the start of the therapy in one patient, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or determined or the continuation of the therapy is determined. The rate at which the concentration of free GPC3 after the start of the GPC3-targeting drug therapy is equal to or larger than that before the start of the therapy can be appropriately ed by those skilled in the art and is not limited to a particular value. Such a rate can be riately selected from a numerical range of 1 time to 106 times. When the rate is, for example, 1 time or more, 1.05 times or more, 1.1 times or more, 1.2 times or more, 1.3 times or more, 1.4 times or more, 1.5 times or more, 1.6 times or more, 1.7 times or more, 1.8 times or more, 1.9 times or more, 2 times or more, 2.1 times or more, 2.2 times or more, 2.3 times or more, 2.4 times or more, 2.5 times or more, 2.6 times or more, 2.7 times or more, 2.8 times or more, 2.9 times or more, 3 times or more, 3.1 times or more, 3.2 times or more, 3.3 times or more, 3.4 times or more, 3.5 times or more, 3.6 times or more, 3.7 times or more, 3.8 times or more, 3.9 times or more, 4 times or more, 4.1 times or more, 4.2 times or more, 4.3 times or more, 4.4 times or more, 4.5 times or more, 4.6 times or more, 4.7 times or more, 4.8 times or more, 4.9 times or more, 5 times or more, 5.1 times or more, 5.2 times or more, 5.3 times or more, 5.4 times or more, 5.5 times or more, 5.6 times or more, 5.7 times or more, 5.8 times or more, 5.9 times or more, 6 times or more, 6.1 times or more, 6.2 times or more, 6.3 times or more, 6.4 times or more, 6.5 times or more, 6.6 times or more, 6.7 times or more, 6.8 times or more, 6.9 times or more, 7 times or more, 7.1 times or more, 7.2 times or more, 7.3 times or more, 7.4 times or more, 7.5 times or more, 7.6 times or more, 7.7 times or more, 7.8 times or more, 7.9 times or more, 8 times or more, 8.1 times or more, 8.2 times or more, 8.3 times or more, 8.4 times or more, 8.5 times or more, 8.6 times or more, 8.7 times or more, 8.8 times or more, 8.9 times or more, 9 times or more, 9.1 times or more, 9.2 times or more, 9.3 times or more, 9.4 times or more, 9.5 times or more, 9.6 times or more, 9.7 times or more, 9.8 times or more, 9.9 times or more, 10 times or more, 11 times or more, 12 times or more, 13 times or more, 14 times or more, 15 times or more, 16 times or more, 17 times or more, 18 times or more, 19 times or more, 20 times or more, 21 times or more, 22 times or more, 23 times or more, 24 times or more, 25 times or more, 26 times or more, 27 times or more, 28 times or more, 29 times or more, 30 times or more, 31 times or more, 32 times or more, 33 times or more, 34 times or more, 35 times or more, 36 times or more, 37 times or more, 38 times or more, 39 times or more, 40 times or more, 41 times or more, 42 times or more, 43 times or more, 44 times or more, 45 times or more, 46 times or more, 47 times or more, 48 times or more, 49 times or more, 50 times or more, 55 times or more, 60 times or more, 65 times or more, 70 times or more, 75 times or more, 80 times or more, 85 times or more, 90 times or more, 95 times or more, 100 times or more, 105 times or more, 110 times or more, 120 times or more, 130 times or more, 140 times or more, 150 times or more, 160 times or more, 170 times or more, 180 times or more, 190 times or more, 200 times or more, 220 times or more, 240 times or more, 260 times or more, 280 times or more, 300 times or more, 320 times or more, 340 times or more, 360 times or more, 380 times or more, 400 times or more, 420 times or more, 440 times or more, 460 times or more, 480 times or more, 500 times or more, 550 times or more, 600 times or more, 650 times or more, 700 times or more, 750 times or more, 800 times or more, 850 times or more, 900 times or more, 950 times or more, 1000 times or more, 2000 times or more, 3000 times or more, 4000 times or more, 5000 times or more, 6000 times or more, 7000 times or more, 8000 times or more, 9000 times or more, 104 times or more, 2 × 104 times or more, 4 × 104 times or more, 6 × 104 times or more, 8 × 104 times or more, 105 times or more, 2 × 105 times or more, 4 × 105 times or more, 6 × 105 times or more, 8 × 105 times or more, or 106 times or more, the efficacy of the GPC3-targeting drug therapy for cancer in the patient is predicted, expected, or ined or the continuation of the therapy is determined.

In a non-limiting aspect, the instruction states that the patient is selected on the basis of a method sing monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the therapy, n when the concentration of free GPC3 is equal to or larger than the baseline concentration, the efficacy of the GPC3-targeting drug therapy is determined. In another miting aspect, the instruction states that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum ed 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the ne concentration, the efficacy of the GPC3-targeting drug therapy is determined.

As described above, the instruction states that when the concentration of free GPC3 is equal to or larger than the baseline concentration, the efficacy of the GPC3- targeting drug therapy is determined. In this case, the instruction may state that the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is also taken into consideration. Specifically, the instruction may state that when the tration of free GPC3 in the patient is equal to or larger than the baseline concentration and the sion level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the t is equal to or larger than a particular evaluation score, the efficacy of the argeting drug therapy is determined. In another non-limiting aspect, the instruction can state that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3- targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration and the expression level of GPC3 in a , particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score, the cy of the GPC3-targeting drug therapy is ined.

In a non-limiting , examples of the case where the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score can e high expression and low or moderate expression (IHC total score: 7 or higher and lower than 7, respectively) in a composite score calculated as a result of staining according to the staining method 1. In a non-limiting aspect, alternative examples of the case where the expression level of GPC3 is equal to or larger than a predetermined immunohistochemical staining score can e GPC3-IHC scores of 1+, 2+, and 3+ calculated as a result of staining ing to the staining method In a non-limiting , the instruction states that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 30 days or 1 month after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is equal to or larger than the baseline concentration, the continuation of the GPC3-targeting drug y is determined. In another miting aspect, the instruction states that the patient is selected on the basis of a method comprising monitoring a concentration of free GPC3 in blood, plasma, or serum isolated 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient d with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration, the continuation of the GPC3-targeting drug therapy is determined.

As described above, the instruction states that when the concentration of free GPC3 is equal to or larger than the baseline concentration, the continuation of the GPC3- targeting drug therapy is determined. In this case, the instruction may state that the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is also taken into consideration. Specifically, the instruction may state that when the concentration of free GPC3 in the t is equal to or larger than the baseline concentration and the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a particular evaluation score, the continuation of the GPC3-targeting drug therapy is ined. In another non-limiting aspect, the ction can state that the patient is selected on the basis of a method comprising ring a concentration of free GPC3 in blood, plasma, or serum ed 2 months, 3 months, 4 months, 5 months, or 6 months after the start of GPC3-targeting drug therapy from the patient treated with the therapy, wherein when the concentration of free GPC3 is 1 time or more to 106 times or more the baseline concentration and the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the t is equal to or larger than a predetermined immunohistochemical staining score, the continuation of the GPC3-targeting drug therapy is determined.

In a non-limiting aspect, examples of the case where the expression level of GPC3 in a tissue, particularly, a cancer tissue (including a liver cancer tissue), isolated from the patient is equal to or larger than a predetermined immunohistochemical staining score can e high expression and low or moderate expression (IHC total score: 7 or higher and lower than 7, respectively) in a composite score calculated as a result of staining according to the staining method 1. In a non-limiting aspect, alternative examples of the case where the expression level of GPC3 is equal to or larger than a predetermined histochemical staining score can include GPC3-IHC scores of 1+, 2+, and 3+ ated as a result of staining according to the staining method after, the present invention will be described ically with reference to Examples. However, the present invention is not limited by these Examples.

[Example 1] GC33 is a recombinant humanized IgG1 monoclonal antibody e of binding to human GPC3 with high affinity (WO2006/006693). In order to confirm the d ose limiting toxicity (DLT) of GC33 in patients with ed and/or recurrent hepatocellular cancer (HCC), a phase-I multicenter clinical trial was carried out (GC-001US test). In this test aimed at confirming safety and/or tolerability in the patients with advanced and/or recurrent HCC, the pharmacokinetic profiles of GC33, and its antitumor effects, and ing for biomarkers, GC33 (2.5 mg/kg to 20 mg/kg) was administered by injection through an intravenous drip to each HCC patient once a week.

The HCC patients subjected to the administration had histologically or cytologically confirmed advanced or metastatic HCC unsuitable for surgical operation and/or curative treatment. Eligible patients were at least 18 years old and exhibited n Cooperative Oncology Group Performance Status of 0 or 1 and Child-Pugh class A or B. The patients also had at least one lesion that was ble according to the response evaluation ia in solid tumors (RECIST). The provision of HCC tumor tissues (needle biopsy ations) for use in GPC3 immunohistochemical staining (GPC3-IHC), appropriate hematopoietic functions (absolute neutrophil count ≥ 1500/µl, platelet ≥ 50000/µl), hepatic functions (total bin ≤ 3 times the normal level, aspartate aminotransferase and alanine aminotransferase ≤ 5 times the normal level, PT-INR ≤ 2.0), and renal functions (serum creatinine ≤ twice the normal level) were evaluated as other criteria. The registered ts excluded pregnant, nursing, or pregnancy test-positive (women who underwent menstruation within 12 months from the ration date were subjected to the ncy test) patients, patients who did not plan to use appropriate fertility control, HIV antibody-positive patients, patients having active infection requiring treatment except for HBV or HCV, patients having other active malignant tumors with a e-free interval shorter than 5 years, patients having a past history of transplantation, patients confirmed to have brain metastasis with symptoms, patients having central nervous system disorder or other mental disorders that interfered with consent or understanding of the protocol, patients who ted central nervous system symptoms attributed to hepatic encephalopathy, and patients who exhibited known hypersensitivity to other antibody drugs or pharmaceutical agents produced using CHO cells.

Alternatively, ts who ed treatment including major surgical operation, radiation therapy, and other herapies within 4 weeks before the administration of the GPC3-targeting drug, patients who received treatment with sorafenib within 2 weeks before the administration, or patients who received needle biopsy within 1 week before the administration were excluded from the ts registered in the GPC3-targeting drug therapy, but were subjected to the GPC3-targeting treatment after a predetermined wash-out period. The protocol was carried out according to the guideline of the Good Clinical ce (GCP) and approved by each ipating ethical committee on clinical trials. All patients signed their names on written informed consent before registration. The patients received the continuous administration of GC33 (each cycle involved four doses of GC33) unless the e progressed or unacceptable toxicity appeared. Tumor was evaluated on the basis of a baseline and repetitively evaluated every two cycles until the disease progressed. The state of the disease was evaluated by principal investigators.

The expression of GPC3 proteins in HCC tumor tissues was evaluated by GPC3 immunohistochemical staining (GPC3- IHC). The median measurement of GPC3-IHC was carried out by Charles River Laboratory (USA). Unstained slides of HCC tumor tissues ed from tumor blocks formalinfixed and paraffin-embedded after excision by needle biopsy in each hospital were subjected to immunohistochemical staining. The histochemical staining approach such as epitope retrieval for the measurement by Charles River Laboratory (USA) was performed ing to a method described in WO2009/116659. The antibodies used were a mouse GC33 antibody and a mouse IgG2a antibody as a negative l antibody 6/006693).

As for GPC3-IHC (staining method 1) carried out by Charles River Laboratory, the respective scores of positive cell rate (PR), staining intensity of cytoplasm (SI-cp) or ng ity of cell membrane (SI-cm), and staining n of cell membrane (Sp-cm) were calculated according to the criteria shown in Table 4 and added on the basis of calculation expressions 1 and 2 to evaluate each stained preparation. The evaluation of each stained preparation was finalized at the Peer review meeting ing three pathologists.

[Table 4] Criterion Evaluation Score Positive cell rate (PR) 0 0 1% or more and less than 20% 1 % or more and less than 50% 2 50% or more 3 Staining intensity (SI) Slightly positive 0 - Cytoplasm (SI-cp) Weakly positive 1 - Cell membrane (SI-cm) Moderately positive and/or weakly positive 2 with strong positivity Moderately positive 3 Strongly ve 4 Staining n of cell Negative 0 membrane (SP-cm) When only a portion of the cell membranes 1 of cells was stained When a portion of the cell membranes of 2 most of these cells was stained and the cell membranes of some of the cells were circumferentially stained When the cell membranes of most of these 3 cells were circumferentially stained (Sp-cm scores were calculated by the evaluation of cell staining in the visual field under microscope using an objective lens with a magnification of 4 or 10) [Expression 3] One out of 20 cases that were registered in this test and received the administration failed to produce a preparation, and 3 of the cases did not contain tumor cells sufficient for evaluation. Finally, 16 cases were able to be evaluated. These cases were divided into two groups on the basis of an IHC total score around 7, which was half the maximum value (14) in staining based on epitope retrieval using autoclaving. The evaluation results of each case are shown in Table 5 and [Table 5] Evaluation by GPC-IHC (IHC total score) The number of patients (percentage to the total number 20) High expression (7 or ) 9 (45%) Low or moderate expression (Lower than 7) 7 (35%) Unevaluable 4 (20%) [Example 2] mor effects were ted by the administration of GC33 in argeting treatment. The durations of GC33 administration to 20 cases as described above are shown in As a result of evaluating the state of the disease, 5-month or longer stable disease (SD) was confirmed in 4 cases.

The expression of GPC3 in tumor tissues was examined for its relation to the antitumor effects of GC33. As a result of showing the relation of the IHC total scores of 16 cases evaluable by GPC3-IHC to the duration of administration, all cases confirmed to have SD in a 5- month or longer period were ed in a high-value group when the 16 cases were divided into two groups (with an IHC total score of 7 or higher and with an IHC total score lower than 7). In addition, the obtained results showed that the percentage of the long-period SD cases in the high-value group was also high (Table 6).

[Table 6] IHC total score High-value group Low-value group 6 or higher 36% (4/11) 0% (0/5) 7 or higher 44% (4/9) 0% (0/7) 8 or higher 50% (3/6) 10% (1/10) 9 or higher 50% (2/4) 17% (2/12) or higher 50% (1/2) 21% (3/14) Subsequently, ssion-free survival duration or progression-free al (PFS) was compared between the group with an IHC total score of 7 or higher and the group with an IHC total score lower than 7. The results showed that the group with an IHC total score of 7 or higher had significantly long PFS (.

Some of the tumor samples thus evaluated were used in the additional evaluation of GPC3-IHC. The median measurement of staining of preparations ed from 14 cases was carried out by Ventana Medical Systems, Inc.

(USA) according to an instruction attached to ypican 3 Mouse GC33 Monoclonal Primary Antibody (Ventana Medical Systems, Inc.) using an automatic staining apparatus BenchMark (manufactured by a Medical Systems, Inc.). In GPC3-IHC (staining method 2) carried out by Ventana l Systems, Inc., the preparations were stained according to the attached instruction and then scored on 4 scales of 0 to 3+ in terms of the degree, intensity, etc. of staining in tumor cells. As a result, distribution shown in Table 7 was [Table 7] GPC3-IHC score The number of ts (percentage to 14 evaluable cases) 3+ 3 (21.4%) 2+ 1 (7.1%) 1+ 7 (50%) 0+ 3 (21.4%) In the staining method 2, cases exhibiting longperiod SD were included at a high percentage and with no omission in a 2+/3+ group when the cases were divided into two groups (with a score of 0 and 1+ and with a score of 2+ and 3+) (Table 8).

[Table 8] GPC3-IHC score High-value group Low-value group 1+/2+/3+ 18% (2/11) 0% (0/3) 2+/3+ 50% (2/4) 0% (0/10) 3+ 33% (1/3) 9% (1/11) [Example 3] The concentration of free GPC3 was measured in the serum of patients who received the administration of GC33 in GPC3-targeting treatment. Mouse anti -GPC3 monoclonal antibodies M3C11 and L9G11 (WO2004/022739) were each diluted into 7.5 µg/mL with an immobilizing buffer (0.05 mol/L sodium bicarbonate, pH 9.6) and then dispensed to a plate at a concentration of 100 µL/well. Then, the plate was left ng at room temperature for 1 hour. Each well was washed three times with a washing buffer (0.05 mol/L tris-buffered saline, pH 8.0, 0.05% Tween-20).

Then, a blocking buffer (25 mmol/L tris-HCl buffer, pH 8.1, 0.5 mmol/L magnesium chloride, 72 mmol/L sodium chloride, 0.05% n 150, 5 mg/mL bovine serum albumin, 0.025% Tween-20, 1% Block Ace) was dispensed thereto at a concentration of 200 µL/well. The plate was left ng at room ature for 2 hours to prepare an antibody-immobilized plate. If the plate was not ately used, the plate was stored at 4°C and then used in the measurement.

The serum of each patient collected in the clinical trial was diluted 4-fold with a diluting buffer (25 mmol/L Cl buffer, pH 8.1, 0.5 mmol/L magnesium chloride, 72 mmol/L sodium chloride, 0.05% ProClin 150, 5 mg/mL bovine serum albumin, 0.025% Tween-20, 0.4% Block Ace) and added to the plate at a concentration of 100 µL/well. The plate was left standing overnight at 4°C.

The GPC3 standard used was recombinant GPC3 with serine residues at ons 495 and 509 substituted by alanine residues so as not to permit the binding of n sulfate sugar chains (Hippo et al., Cancer Res. (2004) 64, 2418-2423).

Subsequently, each well of the plate was washed three times with a washing buffer, and a biotin-labeled lypican-3 polyclonal antibody (manufactured by R&D systems, Inc.) diluted into 0.3 µg/mL with a diluting buffer was added thereto at a concentration of 100 µL/well. The plate was further left standing at 25°C for 1 hour, and each well was washed three times with a washing buffer. Then, HRP-labeled streptavidin (Streptavidin-Poly HRP80; ctured by Stereospecific Detection Technologies (SDT)) diluted with a diluting buffer according to the instruction was added thereto at a concentration of 100 µL/well. The plate was left standing at 25°C for 1 hour. Then, each well of the plate was washed three times with a washing buffer. Then, color was developed using TMB Microwell Peroxidase Substrate System actured by Kirkegaard & Perry Laboratories Inc.) ing to the instruction attached to the kit. The absorbance of the reaction on in each well was measured at 450 nm and 650 nm. A calibration curve prepared on the basis of the standard sample containing the recombinant GPC3 was used to calculate the GPC3 antigen level in the serum of each patient from the obtained absorbance of each well.

[Example 4] Change in the serum concentration of detected free GPC3 calculated in Example 3 is shown in for two groups, i.e., the high-value group and the low-value group, of tumor tissue GPC3-IHC scores determined in Example 2. A large number of cases with a measurable level of free GPC3 was included in the group evaluated as having high sion of GPC3 on the basis of the GPC3- IHC score (). A rise in the tration of free GPC3 or stabilization thereof was observed in cases exhibiting long SD. By contrast, a small number of cases with a measurable level of free GPC3 was included in the group evaluated as having low expression of GPC3 or being negative on the basis of the GPC3-IHC score ().

Progression-free survival on or progressionfree survival (PFS) was compared between a group having a measurable level of GPC3 in serum collected during screening or before initial administration (GPC3-positive group) and a group with a GPC3 level below the detection limit. The PFS of the serum GPC3-positive group before the practice of GPC3-targeting treatment was confirmed to be longer than that of the negative group (). A logrank test was further conducted if the serum GPC3- positive group involved serum in which serum GPC3 was measured after the start of stration of the GPC3- targeting drug. The test results showed that the PFS of this group was significantly longer than that of the negative group (cases with a GPC3 level below the measurement limit, regardless of before or after administration of the GPC3-targeting drug) and the positive group (). le 5] As shown in Tables 9 and 10, serum GPC3-positive high-value groups of GPC3-IHC scores evaluated using the staining method 1 and the staining method 2 were shown to have a higher percentage of long SD than that of the high-value group of HC scores (Tables 6 and 8 to ).

[Table 9] GPC3-IHC (staining Serum GPC3-positive with Others method 1) high IHC value (7 or higher) Serum GPC3 before 60% (3/5) 9% (1/11) administration GPC3 Serum GPC3 after 80% (4/5) 0% (0/11) administration GPC3 [Table 10] GPC3-IHC (staining Serum GPC3-positive with Others method 2) IHC (2-3+) Serum GPC3 before 100% (2/2) 0% (0/12) administration GPC3 Serum GPC3 after 67% (2/3) 0% (0/11) administration GPC3 le 6] In the clinical trial, additional 7 cases (one of which was assessed as having an IHC total score of 6 as a result of final evaluation) were further registered as cases having an IHC total score of 7 or higher in GPC3- IHC on the basis of results of the staining method 1 and Pugh score A. Their serum GPC3 levels were ed according to the method of Example 3. A total of 27 cases that received the administration of the GPC3- targeting drug were evaluated for their PFS in the same way as in Example 4. The relation of the serum GPC3 levels to PFS in these cases was studied using the logrank test. The test results showed that the PFS of a group having a measurable level of serum GPC3 before the administration () and the PFS of a group having a able level of serum GPC3 either before or after the stration () were both significantly longer than that of a group with a serum GPC3 level below the measurement limit.

[Example 7] In order to confirm the efficacy and safety of GC33 in patients with advanced and/or recurrent hepatocellular cancer (HCC), a phase-II multicenter randomized doubleblind placebo-controlled clinical trial which involved administering 1600 mg of GC33 every other week was carried out (NP27884 study), ing adult patients with unresectable advanced or metastatic hepatocellular cancer having a past history of treatment. These patients were randomized to a GC33 group (the fixed dose of 1600 mg was administered every other week after administration of two doses at a 1-week interval; n = 121 cases) or a placebo group (n = 60 cases) at a ratio of 2:1 and stratified to 3 cohorts on the basis of GPC3 expression levels (0, 1+, and 2+/3+) by IHC staining using GPC3-IHC kit (manufactured by Ventana l Systems, Inc.). Primary analysis was carried out at the time of occurrence of progression-free al (PFS) events in 128 cases planned in the protocol.

The HCC patients subjected to the administration had histologically confirmed advanced or metastatic HCC (except for fibrolamellar type) unsuitable for curative therapy (surgical resection, liver transplantation, etc.) and/or local therapy or exacerbated after treatment and had a past y of treatment based on systemic therapy with at least one agent. Eligible ts were at least 18 years old with the capability of providing a tumor sample for GPC3 assay and exhibited Eastern Cooperative Oncology Group Performance Status of 0 or 1 and Child- Pugh class A. The patients also had at least one lesion that was evaluable ing to the response evaluation criteria in solid tumors (RECIST). Appropriate hematopoietic functions (absolute neutrophil count ≥ 1500/µl, platelet ≥ 50000/µl, hemoglobin ≥ 8.0 g/dl), c functions (total bilirubin ≤ 2 mg/dl, aspartate aminotransferase and alanine aminotransferase ≤ 5 times the upper limit of the normal level), and renal functions (serum creatinine ≤ twice the upper limit of the normal level) were evaluated as other criteria. rable female ts were premenopausal female patients confirmed to be negative for a serum pregnancy test conducted within 10 days before the start of administration of the study drug, women without the possibility of pregnancy as a result of surgical contraception or after a lapse of 1 year or longer after menopause, and female patients other than the postmenopausal women nth or longer absence of uation) or the surgically contracepted women (resection of the ovary and/or the uterus), who consented to use two types of appropriate ity control s during clinical trial treatment and for at least 3 months or longer after the completion of stration of the study drug. Registrable male subjects were patients who consented to use fertility control based on the barrier method during clinical trial treatment and for at least 40 days after the completion of administration of the study drug. On the other hand, the registered subjects excluded patients who received major surgical operation within 2 weeks before the stration of the GPC3- targeting drug or did not get over severe disorder, patients confirmed to have brain or leptomeningeal metastasis, patients having a past history of malignant tumor within the last 5 years, patients having active infection requiring treatment except for hepatitis B or hepatitis C, patients having a past history of NCI-CTCAE v4.0 Grade 3 or higher hemorrhage within 4 weeks before the start of administration of the study drug, patients having a past history of organ transplantation including liver transplantation, patients who were scheduled to receive or were receiving the administration of an anticancer agent other than the agent to be administered in this test, patients who ed the administration of an anticancer agent within 2 weeks before trial registration, patients who did not completely get over adverse reactions associated with the preceding locoregional or systemic therapy of hepatocellular cancer, patients under eron therapy, patients who had baseline QTc exceeding 470 ms or ted baseline resting ardia (less than 45 beads/min.), patients who received the administration of an anticoagulant or a thrombolytic agent for therapeutic purposes within 2 weeks before the start of administration of the study drug (except for the administration of the agent at a low dose for the purpose of removing clogs in a catheter or for preventive purposes), pregnant or nursing ts, HIV-positive patients or patients having an AIDS-related e, patients having a past history of hypersensitivity for similar agents (monoclonal antibodies, protein-containing preparations, and e hamster ovary-derived preparations), and ts having a serious comorbidity judged by a principal investigator or a sub-investigator as being possibly worsened due to the study drug.

The protocol was carried out according to the guideline of the Good Clinical Practice (GCP) and ed by each participating ethical committee on clinical trials. All patients signed their names on written informed consent before registration. The patients received the continuous administration of GC33 unless the disease ssed or unacceptable toxicity appeared. Tumor was evaluated on the basis of a baseline and evaluated after 4 cycles, 7 cycles, and 10 cycles from the start of administration and then tively every four cycles until the disease progressed. Each cycle involved two weeks. The state of the disease was ted by principal investigators.

The expression of GPC3 proteins in HCC tumor tissues was ted by GPC3 immunohistochemical ng (GPC3- IHC). The central measurement of GPC3-IHC was carried out by Ventana Medical Systems, Inc. (USA). Unstained slides of HCC tumor tissues prepared from tumor blocks formalin-fixed and paraffin-embedded after excision by needle biopsy in each hospital were subjected to immunohistochemical staining. The antibody used was a mouse GC33 antibody.

[Example 8] In the cases who ed GC33 or a placebo in GPC3- targeting treatment, the serum concentration of free GPC3 was measured before the initial administration using a combination of two types of different antibodies capable of binding to free GPC3 (a combination of a GT30 antibody and a GT607 antibody or a combination of GT114 and GT165).

GT30, GT607, GT114, and GT165 were prepared according to a method described in WO2004/022739 and selected as antibodies capable of binding to free GPC3. The H and L chains of GT30 are shown in SEQ ID NOs: 83 and 84, respectively. The H and L chains of GT607 are shown in SEQ ID NOs: 85 and 86, respectively. The H and L chains of GT114 are shown in SEQ ID NOs: 87 and 88, tively.

The H and L chains of GT165 are shown in SEQ ID NOs: 89 and 90, respectively.

An antibody-bound particle solution containing GT30 or GT114 bound to magnetic particle beads (manufactured by JSR Corp.) was added at a concentration of 25 µL/well to a 96-well microplate. uently, a standard sample solution for a calibration curve (the GPC3 standard described in Example 3 was used) or an appropriately diluted serum sample was added thereto at a concentration of 25 l, and further, ne phosphatase-labeled GT607 or GT165 was added o at a concentration of 25 µL/well. After shaking at 25°C for 20 minutes, each well was washed 5 times with a washing on, with the magnetic beads collected using Dyna-Mag-96 Side Skirted (manufactured by VERITAS Corp.). A luminescent substrate solution preheated to 37°C was added thereto at a concentration of 50 µL/well. The plate was shaken at room temperature for 1 minute and then left standing for 4 minutes to emit light. Chemiluminescence intensity was measured using a luminometer (manufactured by VERITAS Corp.).

A calibration curve ard curve) prepared on the basis of the standard sample containing the recombinant GPC3 was used to calculate the GPC3 antigen level in the serum of each patient from the obtained chemiluminescence ity of each well.

[Example 9] Once the PFS events of 128 cases were obtained from among 125 GC33-administered cases and 60 placeboadministered cases as described above, the effects of administration of GC33 in GPC3-targeting treatment were evaluated on the basis of PFS. In addition, overall survival (OS) was evaluated as a secondary endpoint when reaching 78 events.

The GC33-administered group was further divided into two groups (a group exposed to GC33 at a lower level than a cutoff value: 33-exposed group, and a group exposed to GC33 at a higher level than a cutoff value: high-GC33-exposed group) using, as the cutoff value, the median value 230 µg/ml of projected blood trough levels of GC33 before administration of day 1 in the 3rd cycle (on the 4th week from the start of initial administration) based on population PK models obtained using the serum GC33 concentration values of this phase- II clinical trial. The ssion-free survival duration or progression-free survival (PFS) or the overall survival duration or overall survival (OS) was ed as an index for clinical effects between these groups or n these groups and the placebo group by the Kaplan-Meier method. le 10] The serum concentrations of detected free GPC3 calculated in Example 8 were divided into two groups, i.e., a low-value group and a high-value group, on the basis of the median value of the concentrations measured in a system having GT30 and GT607 in combination. The PFS or OS curves of low-GC33-exposed, high-GC33-exposed, and placebo groups, as shown in Example 9, are shown in FIGs. 7A to 7D. Likewise, the serum concen trations of free GPC3 were divided into two groups on the basis of the median value of the concentrations ed in a system having GT114 and GT165 in combination. The PFS or OS curves of these groups are shown in FIGs. 8A to 8D.

In all cases, the group with a low concentration of free GPC3 exhibited the low effect of prolonging the PFS and OS durations, whereas the high-GC33-exposed group with a high concentration of free GPC3 in serum exhibited significantly low hazard ratios of the PFS and OS durations to the low-GC33-exposed group or the placebo group.

As a result of evaluating the cutoff value of free GPC3 that achieved the smallest significant difference, the cutoff value was 175 pg/mL for the T607 system and 259.7 pg/mL for the GT165 system. The PFS and OS curves of a patient group that exhibited a free GPC3 level higher than the cutoff value in each system are shown in FIGs. 7E and 7F and FIGs. 8E and 8F, respectively. In this case as well, a significantly low hazard ratio, i.e., the prolongation of each survival duration, was ted in the high-GC33-exposed group.

All publications, patents, and patent applications cited herein are incorporated herein by reference in their entirety.

[Industrial Applicability] The present invention contributes to improvement in the efficacy of GPC3-targeting drug therapy and improvement in QOL of a t to be treated, and is useful in the treatment of cancer including liver cancer.

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Claims

Claims 1.

1. Use of an anti-GPC3 antibody for the manufacture of a medicament for the treatment of a GPC3-expressing cancer patient having a predetermined value of a concentration of free GPC3 in a serum sample isolated from the cancer patient after the start of anti-GPC3 antibody therapy, wherein said predetermined value is a value selected from within the range of 0.4 ng/mL to 1.1297 ng/mL and n, when the concentration of free GPC3 is above the predetermined value, the anti-GPC3 antibody y is determined to be effective or the anti-GPC3 antibody y is determined to be continued.

2. The use according to claim 1, wherein the concentration of free GPC3 is ed using an immunological method.

3. The use according to claim 1 or 2, wherein the concentration of free GPC3 has been increased as a result of receiving the anti-GPC3 antibody therapy.

4. The use according to any of claims 1 to 3, wherein a GPC3 histochemical total staining score of 7 or higher is obtained in cancer tissue isolated from the patient.

5. The use ing to any of claims 1 to 4, wherein the cancer patient is a GPC3-expressing liver cancer patient.

6. The use according to any of claims 1 to 5, wherein the anti-GPC3 antibody has antibody-dependent cellular cytotoxicity (ADCC) activity and/or complement-dependent cytotoxicity (CDC) activity.

7. The use according to any of claims 1 to 6, wherein the anti-GPC3 antibody is an PC3 chimeric antibody or a zed anti-GPC3 antibody comprising any of the following (1) to (5): (1) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 set forth in SEQ ID NOs: 4, 5, and 6, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 set forth in SEQ ID NOs: 7, 8, and 9, respectively; (2) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 set forth in SEQ ID NOs: 12, 13, and 14, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 set forth in SEQ ID NOs: 15, 16, and 17, respectively; (3) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 set forth in SEQ ID NOs: 20, 21, and 22, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 set forth in SEQ ID NOs: 23, 24, and 25, respectively; (4) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 set forth in SEQ ID NOs: 28, 29, and 30, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 set forth in SEQ ID NOs: 31, 32, and 33, respectively; and (5) heavy chain CDR1, heavy chain CDR2, and heavy chain CDR3 set forth in SEQ ID NOs: 36, 37, and 38, respectively, and light chain CDR1, light chain CDR2, and light chain CDR3 set forth in SEQ ID NOs: 39, 40, and 41, respectively.

8. The use according to any of claims 1 to 7, wherein the anti-GPC3 dy comprises any of the ing (1) to (6): (1) a heavy chain variable region selected from the group of heavy chain variable regions set forth in SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region set forth in SEQ ID NO: 51; (2) a heavy chain variable region selected from the group of heavy chain variable regions set forth in SEQ ID NOs: 44, 45, 46, 47, 48, 49, and 50 and a light chain variable region selected from the group of light chain variable regions set forth in SEQ ID NOs: 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, and 66; (3) a heavy chain variable region set forth in SEQ ID NO: 67 and a light chain variable region set forth in SEQ ID NO: 68; (4) a heavy chain variable region set forth in SEQ ID NO: 69 and a light chain variable region set forth in SEQ ID NO: 70; (5) a heavy chain variable region set forth in SEQ ID NO: 71 and a light chain variable region set forth in SEQ ID NO: 72; and (6) a heavy chain variable region set forth in SEQ ID NO: 71 and a light chain le region set forth in SEQ ID NO: 73.

9. The use according to any of claims 1 to 8, wherein the GPC3-targeting drug comprises an anti-GPC3 antibody conjugated with a cytotoxic substance.