EP1506012A1

EP1506012A1 - Use of a vaccine for active immunization against cancer

Info

Publication number: EP1506012A1
Application number: EP03722041A
Authority: EP
Inventors: Gottfried Himmler; Hans Loibner; Hellmut Samonigg
Original assignee: Igeneon Krebs-Immuntherapie Forschungs- und Entwicklungs-GmbH
Current assignee: ALTROPUS GmbH
Priority date: 2002-05-21
Filing date: 2003-05-20
Publication date: 2005-02-16
Also published as: AT500647A1; WO2003097092A1; US20050169929A1; NO20040267L; AU2003229346A1

Abstract

The invention relates to the use of a vaccine that is based on a tumor-associated antigen, the epitope, mimotope, and specific or anti-idiotypic antibody thereof for producing a medicament used for prophylactic and/or therapeutic active immunization against cancer in combination with chemotherapy.

Description

USE OF A VACCINE FOR ACTIVE IMMUNIZATION AGAINST CANCER

The invention relates to the use of a vaccine based on a tumor-associated antigen, its epitope, mimotope, specific or anti-idiotypic antibody for the manufacture of a medicament, and a set for the prophylactic and / or therapeutic active immunization against cancer.

Tumor-associated antigens (TAA) are often the basis for the development of immunotherapeutic agents for the prophylaxis and / or treatment of cancer. TAA are structures that are preferentially expressed on the cell membrane of tumor cells, thereby making it possible to differentiate them from non-malignant tissue and therefore are seen as target points for diagnostic and therapeutic applications of specific antibodies. Examples of tumor-associated carbohydrate structures are the Lewis antigens, which are increasingly expressed in many epithelial cancers. These include Lewis x, Lewis b and Lewis y structures, as well as sialylated Lewis x structures. Other carbohydrate antigens are GloboH structures, KHl, Tn antigen, TF antigen, the alpha-1, 3-galactosyl epitope (Elektrophoresis (1999), 20: 362; Curr. Pharmaceutical Design (2000), 6: 485 , Neoplasma (1996), 43: 285).

More TAA. are proteins that are particularly strongly expressed on cancer cells, e.g. CEA, TAG-72, MUCl, Folate Binding Protein A-33, CA125, EpCAM and PSA.

Direct therapeutic applications of antibodies against TAA are based on passive immunotherapy, which means that a specific antibody is administered systemically in a suitable amount to cancer patients and has a therapeutic effect only as long as the concentration in the organism is sufficiently high for this. The biological half-life of such agents depends on their structure and ranges from a few hours to several days. It is therefore necessary to carry out repeated applications. When using xenogenic antibodies (e.g. murine monoclonal antibodies, MAK), however, this leads to undesirable immune reactions that neutralize a possible therapeutic effect and dangerous side effects (anaphylactic Reactions). Therefore, such immunotherapy drugs can only be administered for a limited time.

Another approach to cancer immunotherapy is to selectively activate the immune system of cancer patients to fight malignant cells. This is attempted using various forms of cancer vaccines. This includes vaccinations with autologous or allogeneic tumor cells, chemically or molecular biologically modified autologous or allogeneic tumor cells, isolated or produced with the help of chemical or molecular biological methods, TAA derived therefrom, recently also vaccinations with DNA coding for TAA or structures derived therefrom, etc. An alternative method is based on the use of anti-idiotypic antibodies for vaccination against cancer. Suitable anti-idiotypic antibodies can immunologically mimic a TAA. As foreign proteins (e.g. urine antibodies, goat antibodies etc.), they induce a strong immune response in humans after vaccination - in contrast to the actual human tumor antigens, which are often only slightly immunogenic as self-structures. Therefore, anti-idiotypic antibodies can be used as an immunogenic replacement of a tumor antigen for vaccination.

In contrast to passive immunotherapies with anti-tumor antibodies, very small amounts of a suitable vaccine are in principle sufficient for active specific cancer immunotherapy to induce immunity for months to years, which can be refreshed if the booster vaccine weakens. In addition, both humoral and cellular immunity can be induced with active immunization, the interaction of which can result in an effective protective effect.

In summary, the previous use of antibodies or their derivatives in cancer immunotherapy is essentially based on two principles:

• Passive therapy with antibodies or their derivatives that are directed against TAA. Tumor cells are destroyed relatively specifically (Immunology Today (2000), 21: 403-410; Curr. Opin. Immunol. (1997), 9: 717).

• Active immunization (vaccination) with TAA or antibodies or their derivatives, which are directed against the idiotype of antibodies with specificity against TAA. Active vaccination triggers an immune response against TAA. This immune response is therefore also directed against the corresponding tumor cells (Ann. Med. (1999), 31:66; Im unobiol. (1999), 201: 1).

In the course of the discovery and subsequent characterization of a wide variety of TAA, it has emerged that these have important functions for cancer cells. They enable the degenerated cells to have characteristic properties for the malignant phenotype, e.g. exercise increased adhesiveness, which are of great importance for the establishment of metastases. However, at certain stages, such antigens can also be expressed on normal cells, where they are responsible for normal functions of these cells. Without claiming to be complete, here are some examples of such antigens:

• N-CAM (Neuronal Cell Adhesion Molecule), which is often expressed on tumors of neuronal origin and causes homophilic adhesion (J. Cell Biol. 118 (1992), 937).

• The Lewis Y carbohydrate antigen, which appears on the majority of tumors of epithelial origin, but also plays an important role during the fetal development of epithelial tissues. The expression of this antigen in lung cancer has been shown to be strongly associated with an unfavorable prognosis, since Lewis Y positive cancer cells obviously have a higher metastatic potential (N. Engl. J. Med. 327 (1992),

14).

• CEA (Carcino Embryonic Antigen), which occurs frequently on epithelial tumors of the gastrointestinal tract and has been identified as a self-adhesion molecule (Cell 57 (1989), 327).

• Ep-CAM (Epithelial Cell Adhesion Molecule), which is expressed on almost all tumors of epithelial origin, but also occurs on many normal epithelia, which is known as Self-adhesion molecule was characterized and can therefore be classified as pan-epithelial adhesion antigen (J. Cell Biol. 125 (1994), 437).

WO 00/41722-A1 describes the use of antibodies directed against human cellular membrane proteins for the active immunization of cancer patients. Under it is a vaccine containing the murine onoclonal antibody HE2, directed against the Ep-CAM molecule.

Anti-Ep-CAM antibodies are also used for passive immunotherapy. EP 0 755 683-Al describes the treatment with a high antibody dose in combination with chemotherapy, radiotherapy or surgery.

In the same way, an antibody directed against the "epidermal growth factor" Receptor-2 (HER-2) is used for passive immunotherapy in combination with chemotherapy (Anticancer Drugs 2001, 12 Suppl 4: S3-10).

Passive immunotherapy is also described in WO 01/07082, also in combination with a chemotherapeutic agent which is intended to arrest cells expressing Ep-CAM in the S or G2 / M cell cycle phase.

Current Opinion in Molecular Therapeutics 2000, 2 (4): 453-458 and US 5,747,048, on the other hand, describe active immunization with a vaccine that contains a synthetic facial expression of the mucin-associated glycan epitope SialylTn conjugated to a carrier molecule. This vaccine actively induces an immune response, especially if the patient has previously undergone chemotherapy.

In US 5,792,455 and in Clin. Cancer Res. , 1999, 5, 1319-1323 describes the use of a monoclonal IgG2b antibody, BEC2, which is a facial expression for GD3, for the treatment of melanoma or small cell lung cancer (SCLC), inter alia in combination with chemotherapy. The BEC2 antibody is administered with BCG / Bacillus Calmette-Guerin, which is a very potent immunogenic adjuvant. Here are treated with the antibody in combination with adjuvants, which have a very strong immunogenic effect, sometimes have strong side effects such as fever and an increase in glucose levels.

Chemotherapy itself is used to treat cancer patients to chemically combat dividing tumor cells. Disseminated tumor cells that are at rest are not attacked by chemotherapy ("minimal residual disease"), but are associated with the formation of metastases. The professional community is therefore increasingly concerned with immunotherapy to combat disseminated tumor cells.

The object of the present invention is to improve the use of vaccines for the active immunization of cancer patients.

This object is achieved by the provision of the embodiments described in the claims.

According to the invention, a vaccine based on a tumor-associated antigen (TAA), its epitope, mimotope, specific or anti-idiotypic antibody is used to produce a medicament which is used for the prophylactic and / or therapeutic active immunization against cancer in combination with chemotherapy.

The TAA is preferably from the group of peptides or proteins, in particular EpCAM, NCAM, CEA and T-cell peptides, carbohydrates, in particular Lewis Y, sialyl-Tn, GloboH, and glycolipids, in particular GD2, and GM2, and epitopes or Mimotopes of these antigens are selected. The TAA used in the vaccine according to the invention preferably induce a functional immune response directed against tumor cells. Thereby not only tumor cells should be attacked during cell division, but also at rest, for the effective treatment of "minimal residual disease" or reduction of the potential for metastasis.

The aim of the combined immunotherapy according to the invention is in any case functionally support the immune system in order not only to bind the induced antibodies to the tumor cells, but also to reduce them by means of a humoral or cellular immune response. The competitive binding of an antibody to a receptor of a tumor cell with tyrosine kinase activity is considered insufficient. Ultimately, immunotherapy should not only block a receptor and prevent enzymatic cell division, but also eliminate tumor cells, for example by lysis.

Within the scope of the present invention, therefore, those structures of possible TAA are excluded which only represent receptor proteins with tyrosine kinase activity, the immune complex formation of which is intended to inhibit the enzymatic reaction for cell division. Receptor proteins are derived, for example, from HER-2 or the similar receptor c-erbB-2, which have tyrosine kinase activity and support cell division. Receptor protein TAA of this type, or their facial expressions or anti-idiotypic antibodies, therefore attack the dividing cell, just like chemotherapy. As an example of this, EP 1006194 describes the gp75 protein derived from the c-erbB-2 receptor, which alone or in combination with chemotherapy is said to prevent cell division.

The epitopes primarily mimic or comprise domains of a natural, homologous or derivatized TAA. These are at least comparable to the TAA in terms of their primary structure and possibly their secondary structure. However, the epitopes can also differ completely from the TAA, and mimic components of a TAA, especially protein or carbohydrate antigens, purely through the similarity of spatial (tertiary) structures. The tertiary structure of a molecule alone can form facial expressions that elicit the immune response against a specific TAA.

As a rule, it can be assumed that an antigen that mimics a protein epitope of a tumor-associated antigen is to be understood as a polypeptide of at least five amino acids. Preferred TAA are derived from antigens which are specific for epithelial tumors and which occur more frequently in breast cancer, cancer of the stomach and intestine, the prostate, pancreas, ovaries and the lungs. Among the preferred TAA are those which primarily cause a humoral immune response, that is to say a specific antibody formation in vivo. On the other hand, those antigens which generate a T cell-specific immune response can also be selected within the meaning of the invention. These include primarily intracellular structures and T cell peptides.

According to the invention, epithelial cancer, such as breast cancer, cancer of the stomach and intestine, the prostate, pancreas, ovaries and lungs, for example SCLC ("small cell lung cancer") and NSCLC ("non-small cell lung cancer"), is preferably dealt with.

Further preferred proteinaceous TAA, which are particularly expressed on cancer cells of solid tumors, are e.g. TAG-72, MUCl, Folate Binding Protein A-33, CA125, PSA, MART etc. (see e.g. Sem. Cancer Biol. 6 (1995), 321). Furthermore, so-called T-cell epitope peptides (Cancer Metastasis Rev. 18 (1999), 143; Curr. Opin. Biotechnol. 8 (1997), 442; Curr. Opin. Immunol. 8 (1996), 651) or Mimotopes of such T cell epitopes (Curr. Opin. Immunol. 11 (1999), 219; Nat. Biotechnol. 16 (1998), 276-280) are used. Suitable TAA are expressed in at least 20%, preferably at least 30% of the cases of tumor cells of a specific cancer type, more preferably in at least 40%, in particular in at least 50% of the patients.

Carbohydrate epitopes preferred according to the invention are tumor-associated carbohydrate structures, such as the Lewis antigens, e.g. Lewis x, Lewis b and Lewis y structures, as well as sialylated Lewis x structures. Furthermore, GloboH structures, KH1, Tn antigen or sialyl-Tn, TF antigen, the alpha-1-3, galactosyl epitope are preferred carbohydrate antigen structures in the context of the present invention.

In a particular embodiment, according to the invention, at least two identical or different epitopes of an adhesion protein, such as a homophilic cellular Membrane protein, such as EpCAM, provided or imitated in the vaccine. Active immunization can thus generate a large number of antibodies with specificity for the same molecule but different EpCAM binding sites.

The vaccine can also contain a glycosylated antibody, especially if the glycosylation itself can also mimic an epitope of a carbohydrate epitope of a TAA. It has been found that an epitope of an EpCAM protein and an epitope of a Lewis carbohydrate component, for example Lewis Y, or with the sialyl-Tn carbohydrate antigen are preferably combined. In particular, a Lewis Y-glycosylated antibody with a specificity for an EpCAM structure represents a particularly good immunogen in a vaccine formulation used according to the invention. This antibody can mimic cellular tumor antigens particularly well and accordingly brings about the desired immune response for inhibiting epithelial tumor cells.

According to the invention, the vaccine is used for active immunization and is therefore administered only in small amounts. For example, no particular side effects are expected, in particular no fever or an increase in the level of glucose, even if the immunogenic active substance used according to the invention is derived from a non-human species, such as a murine antibody. However, it is assumed that a recombinant, chimeric, as well as a humanized or human active ingredient combined with murine and human components is particularly compatible for administration to humans. On the other hand, a murine portion of the active substance can provoke the immune response in humans due to its strangeness.

The term “antibody” is understood to mean antibodies of all kinds, in particular polyclonal or monoclonal or also chemically, biochemically or molecularly biologically produced antibodies.

Although the vaccine used according to the invention naturally contains an active ingredient derived from a native antibody who has possibly been isolated from an organism or patient, an antibody derivative is often used, which is preferably selected from the group of antibody fragments, conjugates or homologues, but also complexes and adsorbates. In any case, it is preferred that the antibody derivative contains at least parts of the Fab fragment, preferably together with at least parts of the F (ab ') 2 fragment, and / or parts of the hinge region and / or the Fc part of a lambda or kappa antibody. Furthermore, a single-chain antibody derivative, for example a so-called "single chain" antibody, can also be used in a vaccine in the sense of the invention. An antibody of the type of an immunoglobulin, such as an IgG, IgM or IgA, is preferably used. An IgG2a antibody is particularly preferably used, since IgG2a antibodies show a particularly good complementation and this leads to an increased immunogenicity of the vaccine. This has the further advantage that the antibody content in the vaccine can be further reduced.

According to the invention, a vaccine is preferably also used which contains an antibody or antibody derivative directed against a tumor-associated antigen, ie an abl. The specificity of the antibody is preferably selected from the groups of TAA mentioned above, in particular selected from the group of EpCAM, NCAM, CEA and Lewis Y or sialyl-Tn antigens. A particularly preferred antibody is the HE2 antibody, as described in WO 00/41722. This is directed against the Ep-CAM protein and can also cause an anti-Ep-CAM immune response in a vaccine formulation as an immunogen.

A particularly good immunogen for EpCAM is, for example, an anti-EpCAM antibody that imitates or has at least one or at least two EpCAM epitopes, for example due to its EpCAM-like idiotype. Such an antibody is derived, for example, from an anti-EpCAM antibody from WO 00/41722.

A preferred vaccine contains an antibody that specifically binds an antibody. The Tumorvakz ^'ine thus includes inter anti-idiotype Antibodies, i.e. ab2, for active immunization. Anti-idiotypic antibodies used according to the invention preferably recognize the idiotype of an antibody which is directed against a TAA. An epitope of a TAA is thus already formed on the paratope of the anti-idiotypic antibody as facial expressions for the TAA.

Here too, the preferred selection from the TAA groups mentioned above is made. For example, an anti-idiotypic antibody against glycan-specific antibodies is used, such as an anti-idiotypic antibody that recognizes the idiotype of an anti-Lewis Y antibody, e.g. as described in EP 0 644 947.

The vaccine used according to the invention is advantageously in a suitable formulation. Such formulations with a pharmaceutically acceptable carrier are preferred. This includes, for example, auxiliaries, buffers, salts, preservatives. The vaccine can e.g. B. for the prophylaxis and therapy of cancer-associated disease states such as the formation of metastases and "minimal residual disease" of cancer patients. Thereby, antigen-presenting cells are specifically modulated in vivo or ex vivo in order to specifically generate the immune response against the TAA and the tumor cells.

A vaccine formulation which is preferably used according to the invention mostly contains the immunogenic active substance only in small concentrations, for example in an immunogenic amount in the range from 0.01 μg to 10 mg. Depending on the nature of the TAA, its epitope, mimotope, specific or anti-idiotypic antibodies, depending on the use of non-species sequences or derivatization, but also on the auxiliaries or adjuvants used, the suitable immunogenic dose is selected, for example in the range from 0.01 μg to 750 ug, preferably 100 ug to 500 ug. A depot vaccine that is to be released to the organism over a longer period of time can also contain much higher amounts of antibody, for example at least 1 mg to more than 10 mg. The concentration depends on the amount of liquid or suspended administered Vaccine. A vaccine is usually in pre-filled syringes with a volume of 0.01 to 1 ml, preferably 0.1 to 0.75 ml, of the concentrated solution or suspension.

The vaccine used according to the invention preferably presents the immunogen in a pharmaceutically acceptable carrier which is suitable for subcutaneous, intramuscular but also intradermal or transdermal administration. Another type of administration works via the mucosal route, such as vaccination by nasal or oral administration. If solids are used as auxiliaries for the vaccine formulation, an adsorbate or a suspended mixture of the antibody with the auxiliaries is administered. In particular embodiments, the vaccine is presented as a solution or liquid vaccine in an aqueous solvent.

One or more vaccine units of the tumor vaccine are preferably already provided in suitable pre-filled syringes. Since an antibody is relatively stable compared to TAA, vaccines based on antibodies or their derivatives have the significant advantage that they can be marketed as ready-to-use solutions or suspensions in a ready-to-use form , A content of preservative, such as thimerosal or other preservatives with improved tolerability, is not necessarily necessary, but can be provided in the formulation for longer shelf life at storage temperatures from refrigerator temperatures to room temperature. However, the vaccine used according to the invention can also be made available in frozen or lyophilized form, which can be thawed or reconstituted if necessary.

In any case, it has proven useful to increase the immunogenicity of the active ingredient used according to the invention by using adjuvants in the vaccine formulation. Vaccine adjuvants suitable for this purpose are preferably aluminum hydroxide (aluminum gel) or phosphate, also growth factors, lymphokines, cytokines, for example IL-2, IL-12, GM-CSF, gamma interferon, or Complement factors such as C3d, further liposome preparations, but also formulations with additional antigens against which the immune system has already given a strong immune response, such as tetanus toxoid, bacterial toxins such as Pseudomonas exotoxins and derivatives of lipid A.

An adjuvant is preferred which enables the drug to be administered without side effects. The term side effects includes, for example, increased glucose levels or fever; local redness at the site of administration or slight swelling are not seen as a particular side effect.

Known methods for conjugating or denaturing vaccine components can also be used for the vaccine formulation in order to further increase the immunogenicity of the active substance.

Particular embodiments of the vaccine used according to the invention contain further vaccine antigens, in particular additionally anti-idiotypic antibodies, and also mixtures of immunogenic antibodies with different antibodies, which are administered simultaneously.

The vaccine is preferably used at the beginning of chemotherapy. Vaccination can be started at the time of any surgery or before surgical removal of tumor tissue. Thus, protection against possible dissemination of tumor cells by specific antibodies can be built up at the time of the operation. Chemotherapy is preferably started within 1 to 2 weeks. Vaccination simultaneously with and / or during chemotherapy is also preferred for practical reasons. The patient is already in clinical treatment, the additional therapeutic measures can be carried out in a simple manner.

If immunotherapy is already on the first day of chemotherapy or within the first 2 to 3 days, this can happen Immune systems are activated at an early stage before the organism is affected by chemotherapy. Chemotherapy is indeed associated with side effects, such as that of a weakened immune system, resulting in an increased

Patients are susceptible to infection. It was precisely for this reason that it was surprising that immunotherapy can be used successfully immediately before and during chemotherapy. It was observed that the immune response after vaccination with a tumor vaccine on the first day, several hours before the start of chemotherapy, could be induced to the same extent as without chemotherapy treatment. The serum content of Im unglobulins and vaccine antigen-specific antibodies was in any case persistently increased, regardless of chemotherapy. There was even evidence that the specific immune response was enhanced by chemotherapy.

The vaccine administration scheme according to the invention preferably includes not only the initial vaccination in the context of chemotherapy, but also several booster vaccinations at certain time intervals, which for practical reasons may possibly be the same as the intervals of the chemotherapy. Even after chemotherapy, long-term immunotherapy for months and years is a very suitable scheme. Both the initial vaccination and subsequent booster vaccinations are preferably carried out with the same vaccine.

The combination with adjuvant or palliative chemotherapy is preferred. The combination with monotherapy or polytherapy is possible. For reasons of the different mechanisms of action, the vaccine is preferably combined with polychemotherapy.

Agents that are preferably used for chemotherapy are alkylating pharmaceutical preparations. For example, agents containing taxane, anthracycline or platinum are preferred. All of the usual preparations that are used for the various cancer treatments can be combined according to the invention. The chemotherapy drugs are usually administered intravenously or orally. Oral forms of administration of the Chemotherapeutic agents can possibly also be administered according to the invention as a combination preparation with the oral form of the vaccine.

A functional immune response is caused by the vaccine used according to the invention, which is mainly carried by the humoral immune system. An immediate reaction is an increased mmunglobulin titer in the patient's serum. Above all those antibodies occur in serum which are specific for the vaccine antigen. A cellular immune response can be detected with the usual test systems. In any case, it can be demonstrated that tumor cells can be bound specifically. The number of tumor cells found in blood or bone marrow is said to be reduced even by the specific immune response.

Vaccination for the purposes of the present invention can in principle be carried out both for therapeutic and for prophylactic treatment (as with all antimicrobial vaccines). This means that the vaccination against cancer according to the invention can be understood both as a therapeutic and as a prophylactic application. Thus, by vaccinating people not suffering from cancer with suitable antibodies, preventive protection against the outbreak of cancer-associated disease states, in particular the formation of metastases, can be achieved. Such prophylactic vaccination is particularly, if not exclusively, possible for people who have an increased, possibly genetic risk of developing cancer.

In a preferred embodiment, the vaccine used according to the invention contains a human cellular membrane antigen or an antibody against this membrane protein or a corresponding anti-idiotypic antibody. Such a membrane protein plays a role in adhesion processes. Adhesion processes are preferably cell-cell interactions, with ligands or receptors on the cell surface being involved. Adhesion molecules are accordingly the cell-cell interaction serving ligands or receptors on the cell surface. A subset of such

Adhesion molecules are the self-adhesion molecules. These have the property of being able to bind to themselves.

The physiological effect of an immune response induced by vaccination with an antibody against a TAA naturally depends on the function of the respective TAA. For example, the TAA has a function as a receptor for the adhesion of tumor cells, in particular to a ligand on endothelial cells of the vascular system (such a property is important for the ability of the infected cancer cells to exit the vascular system and settle in tissue in order to undergo metastasis then this adhesiveness is reduced by vaccination with a suitable antibody against this TAA, because there are permanently induced antibodies in the circulation and in the tissue which compete with the interaction of the TAA with its ligand, since they mimic the TAA in soluble form.

According to the explanations above, vaccination with suitable TAA or corresponding antibodies, which have a function for the malignancy of tumor cells, can result in the induced immune response interfering with the function of the TAA in its interaction with its ligand and making it difficult or preventing it. This means that cancer cells cannot or do not have sufficient properties important for the malignant phenotype, which can slow down or stop the development of the disease and, especially in the early stages, suppress metastasis and reduce metastases in the late stage of metastatic cancer can be.

In a further preferred embodiment, the cellular membrane antigen is capable of self-adhesion, ie certain epitopes of the antigen are responsible for homophilic binding to the same antigen on another cell. Examples of such antigens include N-CAM (Neuronal Cellular Adhesion Molecule), CEA (Carcino Embryonic Antigen) and Ep-CAM (Epithelial Cell Adhesion Molecule). Antibodies against Epitopes directed by self-adhesion antigens which are involved in this function can, according to the above statements, carry complementary structural information of such an epitope. Therefore, in accordance with the above statements, vaccination with such vaccine antigens can induce the formation of antibodies which carry the properties of this self-adhesion in the binding reaction. This means that such induced antibodies can in turn bind to the self-adhesion antigen, since in such a case the receptor and ligand are identical. Vaccination of cancer patients with suitable antibodies against self-adhesion antigens may thus induce an immune response, which in turn binds directly to tumor cells and thus triggers a variety of therapeutic effects. On the one hand, the ability of self-adhesion, which is important for malignant cells, is blocked, and on the other hand, by binding the induced antibodies to the cancer cells, human effector functions such as complement-dependent lysis and / or lysis can be triggered by activating cytotoxic effector cells, which lead to the destruction of the cancer cells.

Through all of the above mechanisms and effects, vaccination of cancer patients with suitable TAA or corresponding antibodies against TAA or anti-idiotypic antibodies can suppress the formation of new metastases and at least slow the dissemination of the disease. In the early stages of the disease, for example shortly before or after successful surgery of a primary tumor (adjuvant stage), such disseminated tumor cells prevent such vaccinations from establishing themselves as new metastases. The combination with chemotherapy according to the invention on the one hand kills the dividing active tumor cells. On the other hand, the relapse-free lifespan and thus the overall survival of such patients can be extended through targeted immunotherapy. Vaccinations of this type and booster vaccinations carried out at suitable intervals can possibly provide lifelong protection against the formation of metastases. Vaccinations of cancer patients are of particular interest suitable TAA or corresponding antibodies against a self-adhesion TAA, since in these cases, as described above, an additional direct attack of the induced immune response on tumor cells enables an increased therapeutic effect.

Methods for finding suitable antigenic structures, modeling and producing the peptides, polypeptides or proteins derived from TAA or nucleic acids coding therefor, further lipoproteins, glycolipids, carbohydrates or lipids are known to the person skilled in the art and can be used for the respective tumor-specific structure without undue experimentation to provide. Furthermore, the methods for formulating a vaccine are known which are suitable for the method according to the invention.

The TAA, its derivatives, epitopes and facial expressions can come from natural or synthetic sources. The antibody components can also be synthesized chemically and then connected to epitope structures or synthesized together. In the case of chemical synthesis of antibody carrier molecules, it is possible to introduce reactive groups at special sites in order to be able to control both the extent of the coupling to an epitope and the type and location of the binding.

Immunogenic TAA, their epitopes, facial expressions or antibodies can also be genetically engineered as recombinant molecules. By genetically modifying nucleic acids that code for native molecules, suitable derivatives can be produced. A recombinant gene product with corresponding tumor-associated glycan structures can also be glycosylated by production in cells which are genetically modified in such a way that they glycosylate proteins accordingly. Such cells can be natural isolates (cell clones), which can be found by appropriate screening for the desired glycosylation. However, cells can also be modified in such a way that they express corresponding enzymes which are necessary for the desired glycosylation in such a way that the desired glycosylation on the recombinant polypeptide or protein can be found (Glycoconj. J. (1999), 16: 81). However, it is also possible to enzymatically produce or change the glycosylation pattern of proteins (Clin. Chem. Lab. Med. (1998), 36: 373).

According to a special embodiment of the present invention, the vaccine used according to the invention comprises a nucleic acid molecule as facial expression for a TAA, the nucleic acid molecule coding for a proteinaceous TAA in the sense of the present invention. The DNA vaccine obtained, like tumor vaccines, is administered on a protein basis.

The present invention also relates to a set which is suitable for the prophylactic and / or therapeutic treatment of cancer-associated disease states. This set contains a) a vaccine based on a tumor-associated antigen, its epitope, mimotope, specific or anti-idiotypic antibody, and b) an agent for chemotherapy.

The components of the set according to the invention and their combination are selected as described above.

The set preferably further comprises suitable application devices, such as e.g. Syringes, infusion devices, etc. If the vaccine is in lyophilized form, the set also contains a suitable reconstitution solution, which may have special stabilizers or reconstitution accelerators. The further preferred set contains several units of the vaccine used according to the invention, which are used for the initial vaccination and for one or more, preferably up to three booster vaccinations.

However, the number of repeated vaccinations can be higher, for which sets containing several vaccination units alone are offered without a combination with chemotherapy. The frequency is optionally in the range from 1 to 12 per year, particularly preferably in the range from 4 to 8 per year. The Dosage can remain the same or decrease.

Booster shots can be carried out at regular intervals, generally for life. Suitable intervals are in the range of about 6 to 24 months and can be determined by monitoring the titer of the induced antibodies (refresh should take place as soon as the titer of the induced antibodies has dropped significantly).

Clinical trials are described below which demonstrate that vaccination of patients immediately prior to chemotherapy with a specific murine MAK (HE2), which is directed against the self-adhesion TAA Ep-CAM, leads directly to the induction of antibodies which selectively respond to the Bind Ep-CAM molecule. This immune response is at least as good in combination with chemotherapy as without chemotherapy. An improvement through simultaneous chemotherapy is even observed. It is shown by way of example, but without any restriction, that vaccination with suitable TAA or antibodies against a TAA, or their derivatives, which at least contain the idiotype of the starting antibody, induces an immune response which can be combined with chemotherapy.

For this purpose, the murine monoclonal antibody HE2 was generated according to standard hybridoma technology methods described per se (see WO 00/41722). Balb / c mice were immunized with human colorectal cancer cells according to standard protocols. The spleen cells were fused with the mouse myeloma line P3X63Ag8 and hybridomas were selected which produce antibodies which selectively bind to human colorectal cancer cells but not to melanoma cells. Ultimately, a hybridoma was selected that secretes an IgG2a / kappa antibody. This antibody (HE2) binds to Ep-CAM, e.g. by Western blot analysis with membrane preparations of KATO III gastric cancer cells in comparison with a known anti-Ep-CAM antibody (KS1-4).

Figure 1 shows the immune serum globulin content of patients who were vaccinated with HE2 with and without simultaneous

Chemotherapy.

FIG. 2 shows the content of IgG directed against HE2 in serum.

FIG. 3 shows the content of IgG directed against HE2 in serum which specifically binds to recombinant Ep-CAM.

FIG. 4 shows the influence of chemotherapy and vaccination on the survival rate in patients with colorectal cancer, stage

4th

The following examples are intended to illustrate but not limit the present invention:

Example:

Example 1: Treatment of cancer patients with HE2 in combination with chemotherapy

Patients with metastatic epithelial cancer were treated subcutaneously with chemotherapy as well as immunotherapy by active immunization with a vaccine containing HE2. Patients received an initial vaccination on day 1 of chemotherapy, at least 1 hour before treatment with the chemotherapy drug. Chemotherapy was administered adjuvantly or palliatively.

On day 1, 15, 29, 57 and 71, serum was withdrawn from the patient to determine the immune response. The results of the determinations are shown in FIGS. 1 to 3.

At the same time, the simultaneous chemotherapy did not show any deterioration in the immune response. A somewhat increased specific immune response was also tended to be found.

Example 2: Treatment of cancer patients with HE2 in combination with chemotherapy

Patients with metastatic, epithelial cancer (colorectal cancer, stage 4) received both chemotherapy and immunotherapy through active immunization with a Vaccine containing HE2 treated subcutaneously, immunization took place on days 1, 15, 29 and 57, after which the vaccinations were repeated every 4 months. Chemotherapy was administered adjuvantly or palliatively.

The survival rate was determined as the primary endpoint of the study, the results are shown in FIG. 4 (n is the number of patients, CT is chemotherapy). It was shown that both with and without chemotherapy, the survival time was significantly increased by treatment with the vaccine. The survival rate after one year was approximately 44% in patients who received chemotherapy only, but the survival rate after more than 80% was found after one year in patients with chemotherapy and immune response to the administration of the vaccine.

Claims

claims:

1. Use of a vaccine based on a tumor-associated antigen, its epitope, mimotope, specific or anti-idiotypic antibody for the manufacture of a medicament for the prophylactic and / or therapeutic active immunization against cancer in combination with chemotherapy.

2. Use according to claim 1, characterized in that the tumor-associated antigen is selected from the group of peptides or proteins, T-cell peptides, carbohydrates, glycolipids and epitopes or mimotopes of these antigens.

3. Use according to claim 1 or 2, characterized in that the vaccine contains an antibody or antibody derivative directed against a tumor-associated antigen.

4. Use according to claim 1 or 2, characterized in that the vaccine contains an anti-idiotypic antibody or its derivative directed against antibodies specific for a tumor-associated antigen.

5. Use according to one of claims 1 to 4, characterized in that the vaccine is administered before and / or during chemotherapy.

6. Use according to claim 5, characterized in that the vaccine is administered further after chemotherapy.

7. Use according to one of claims 1 to 6, characterized in that adjuvant or palliative chemotherapy is carried out.

8. Use according to one of claims 1 to 7, characterized in that a poly-chemotherapy is carried out.

9. Use according to one of claims 1 to 8, characterized in that the chemotherapy is carried out with an agent containing taxane, anthracycline or platinum.

10. Use according to one of claims 1 to 9, characterized in that a functional immune response against tumor cells is induced.

11. Use according to one of claims 1 to 10, characterized in that disseminated tumor cells are reduced.

12. Use according to one of claims 1 to 11, for the prophylactic and / or therapeutic treatment of cancer-associated disease states, in particular the formation of metastases.

13. Use according to one of claims 1 to 12, for the prophylactic and / or therapeutic treatment of epithelial cancer.

14. Use according to any one of claims 1-13, characterized in that the medicament can be administered with an adjuvant without any particular side effects.

15. Set for the prophylactic and / or therapeutic treatment of cancer-associated disease states containing a) a vaccine based on a tumor-associated antigen, its epitope, mimotope, specific or anti-idiotypic antibody, and b) an agent for chemotherapy.

16. Set according to claim 15, characterized in that the tumor-associated antigen is selected from the group of peptides or proteins, T cell peptides, the carbohydrates, the glycolipids and epitopes or mimotopes of these antigens.

17. Set according to claim 15, characterized in that the vaccine contains an antibody directed against a tumor-associated antigen.

18. Set according to claim 15, characterized in that the vaccine is an anti-idiotypic antibody directed against antibodies specific for a tumor-associated antigen contains.

19. Set according to one of claims 15 to 18, characterized in that the vaccine contains the tumor-associated antigen, its epitope, mimotope, specific or anti-idiotypic antibody in an immunogenic amount of 0.01 μg to 10 mg.

20. Set according to one of claims 15 to 19, characterized in that the vaccine contains at least one vaccine adjuvant.

21. Set according to one of claims 15 to 20, characterized in that the vaccine is present in a formulation suitable for subcutaneous, intramuscular, intradermal, transdermal or mucosal, for example for nasal or peroral.

22. Set according to one of claims 15 to 21, characterized in that the agent for chemotherapy contains taxane, anthracycline or platinum.

23. Set according to one of claims 15 to 22, characterized in that the agent for chemotherapy is present in a formulation suitable for intravenous or oral administration.

24. Set according to one of claims 15 to 23, characterized in that several units of the vaccine are included.