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  • A61K31/47—Quinolines; Isoquinolines
  • A61K31/4738—Quinolines; Isoquinolines ortho- or peri-condensed with heterocyclic ring systems
  • A61K31/4745—Quinolines; Isoquinolines ortho- or peri-condensed with heterocyclic ring systems condensed with ring systems having nitrogen as a ring hetero atom, e.g. phenantrolines
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
  • A61K31/47—Quinolines; Isoquinolines
  • A61K31/475—Quinolines; Isoquinolines having an indole ring, e.g. yohimbine, reserpine, strychnine, vinblastine
• • A—HUMAN NECESSITIES
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  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/495—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with two or more nitrogen atoms as the only ring heteroatoms, e.g. piperazine or tetrazines
  • A61K31/505—Pyrimidines; Hydrogenated pyrimidines, e.g. trimethoprim
  • A61K31/513—Pyrimidines; Hydrogenated pyrimidines, e.g. trimethoprim having oxo groups directly attached to the heterocyclic ring, e.g. cytosine
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/55—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
  • A61K31/7042—Compounds having saccharide radicals and heterocyclic rings
  • A61K31/7048—Compounds having saccharide radicals and heterocyclic rings having oxygen as a ring hetero atom, e.g. leucoglucosan, hesperidin, erythromycin, nystatin, digitoxin or digoxin
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
  • A61K31/7042—Compounds having saccharide radicals and heterocyclic rings
  • A61K31/7052—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides
  • A61K31/706—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom
  • A61K31/7064—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom containing condensed or non-condensed pyrimidines
  • A61K31/7076—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom containing condensed or non-condensed pyrimidines containing purines, e.g. adenosine, adenylic acid
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K33/00—Medicinal preparations containing inorganic active ingredients
  • A61K33/24—Heavy metals; Compounds thereof
  • A61K33/243—Platinum; Compounds thereof
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P35/00—Antineoplastic agents

Definitions

• the technical field of the invention is the use of cephalotaxine alkaloids with antiproliferative agents to treat a host with a cellular proliferative disease.
• Conventional antiproliferative agents used in the treatment of cancer are broadly grouped as chemical compounds which (1) affect the integrity of nucleic acid polymers by binding, alkylating, inducing strand breaks, intercalating between base pairs or affecting enzymes which maintain the integrity and function of DNA and RNA; (2) chemical agents that bind to proteins to inhibit enzymatic action (e.g., antimetabolites) or the function of structural proteins necessary for cellular integrity (e.g., antitubulin agents).
• Other chemical compounds that have been identified to be useful in the treatment of some cancers include drugs which block steroid hormone action for the treatment of breast and prostate cancer, photochemically activated agents, radiation sensitizers and protectors.
• Nucleic acid polymers such as DNA and RNA are prime targets for anticancer drugs.
• Alkylating agents such as nitrogen mustards, nitrosoureas, aziridine containing compounds directly attack DNA.
• Metal coordination compounds such as cisplatin and carboplatin similarly directly attack the nucleic acid structure resulting in lesions that are difficult for the cells to repair which, in turn, can result in cell death.
• Other nucleic acid affecting compounds include anthracycline molecules such as doxorubicin, which intercalates between the nucleic acid base pairs of DNA polymers, bleomycin which causes nucleic acid strand breaks, and fraudulent nucleosides.
• Fradulent nucleosides include pyrimidine and purine nucleoside analogs which are inappropriately incorporated into nucleic polymer structures and ultimately cause premature DNA chain termination.
• Certain enzymes that affect the integrity and functionality of the genome can also be inhibited in cancer cells by specific chemical agents and result in cancer cell death. These include enzymes that affect ribonucleotide reductase (e.g., hydroxyurea, gemcitabine), topoisomerase I (e.g. camptothecin) and topoisomerase II (e.g., etoposide).
• cisplatin cis- diamminedichloroplatinum II, CDDP. This compound is active against several human cancers including testicular, small-cell lung, bladder, cervical and head and neck cancer.
• HHT homoharringtonine
• compositions are provided for the treatment of a host with a cellular proliferative disease, particularly a neoplasia.
• a cellular proliferative disease particularly a neoplasia.
• pharmaceutically acceptable cephalotaxine and an antiproliferative agent are administered in an amount sufficient to modulate the cellular proliferative disease.
• FIGURES Figure 1 depicts the general structure of a cephalotaxine analog.
• Rl and R2 represent substitution groups. Structures for Rl and R2 are shown for the cephalotaxine analog,
• Figure 2 depicts the structure of the cephalotaxine analog, Homoharringtonine.
• Figure 3 shows tumor growth delay, as tumor volume on days after treatment with HHT, HHT followed by CDDP, or CDDP alone.
• a pharmaceutically acceptable cephalotaxine is administered, preferably systemically, in conjunction with an antiproliferative agent to improve the anticancer effects.
• the cephalotaxine provides a chemopotentiator effect.
• modulation of a cellular proliferative disease comprises a reduction in tumor growth.
• modulation of a disease comprises inhibition of tumor growth.
• modulation of a cellular proliferative disease comprises an increase in tumor volume quadrupling time (described below).
• modulation of a cellular proliferative disease comprises a chemopotentiator effect.
• modulation of a disease comprises a chemosensitizing effect.
• modulation of a disease comprises cytostasis.
• modulation of a disease comprises a cytotoxic effect.
• a chemical agent is a "chemopotentiator" when it enhances the effect of a known antiproliferative drug in a more than additive fashion relative to the activity of the chemopotentiator or antiproliferative agent used alone. In some cases, a chemosensitizing effect may be observed. This is defined as the effect of use of an agent that if used alone would not demonstrate significant antitumor effects but would improve the antitumor effects of an antiproliferative agent as compared to use of the antiproliferative agent by itself.
• cephalotaxine includes all members of that chemical family including alkaloid derivatives of the Chinese evergreen, Cephalotaxus fortueni and analogs thereof.
• the cephalotaxine family is defined by chemical structure as the ring structures in Figure 1.
• a cephalotaxine analog is further defined but not limited to the structure depicted in Figure 1, having substituent or substitute groups at Rl and R2.
• Rl and/or R2 include esters, including herringtonine, isoharringtonine, homoharringtonine, deoxyharringtonine, acetylcephalotaxine and the like. Table 1 lists structures of Rl and R2 for some of these analogs. Rl and R2 substitutions are typically employed to improve biological activity, pharmaceutical attributes such as bioavailability or stability, or decrease toxicity.
• Rl and/or R2 include alkyl substitutions (e.g., methyl, ethyl, propyl etc.).
• Rl and/or R2 include esters (e.g., methoxy, ethoxy, butoxy, etc.). Rl and R2 are not limited to the above examples, however, in the scope of this invention.
• cephalotaxine analog is a further chemical refinement.
• a specific example of a cephalotaxine analog is homoharringtonine which is the butanediocate ester of cephalotaxine, 4-methyl-2-hydroxy-2-(4-hydroxy-4-methyl pentyl) ( Figure 2).
• antiproliferative agents are compounds which induce cytostasis or cytotoxicity. "Cytostasis” is the inhibition of cells from growing while “cytotoxicity” is defined as the killing of cells.
• Specific examples of antiproliferative agents include: antimetabolites, such as methotrexate, 5-fluorouracil, gemcitabine, cytarabine, pentostatin, 6- mercaptopurine, 6-thioguanine, L-asparaginase, hydroxyurea, N-phosphonoacetyl-L- aspartate (PALA), fludarabine, 2-chlorodeoxyadenosine, and floxuridine; structural protein agents, such as the vinca alkaloids, including vinblastine, vincristine, vindesine, vinorelbine paclitaxel,, and colchicine; antibiotics, such as dactinomycin, daunorubicin, doxorubicin, idarubicin, bleomycins, plic
• Transplantable experimental murine fibrosarcomas (2x10 ⁇ RJF-1 cells) were grown intradermally in the flanks of 3 month old female C3H mice (Charles River, Holister, CA). When the tumors reached a volume of approximately 100 mm , the mice were randomly assigned to each experimental group (4 mice per group).
• the chemopotentiator, homoharringtonine was obtained from NCI and was made to the appropriate concentration in DMSO. Cisplatin (David Bull Laboratories- Mulgrave, Australia, lot. 5201844x) was made to the appropriate concentration in water for injection. The compositions were injected systemically (i.e., intraperitoneally, i.p.), in a volume of 100 microliters. For the treatment of group 3, the chemopotentiator, homoharringtonine, was injected 30 minutes prior to the injection of cisplatin. After treatment, the growth of the tumors was monitored three times per week by caliper measurements of three perpendicular diameters of the tumor and calculation of tumor volume from the formula:
• V ⁇ / 6 x D, x D 2 x D 3 , where Dj_3 is in mm.
• the tumors were followed until they reached a size of four times their day zero treatment volume (TVQT), or up to 30 days after treatment, whichever came first.
• the data is expressed as the "tumor volume quadrupling time" (TVQT) mean and as the “delay.”
• Mean TVQT is the mean days required for individual tumors to grow to four times the tumor volume at the initial treatment day.
• the "delay” is the median of days required for a tumor to grow to four times the mean size of the treated group, minus the median of days required to grow to four times the mean size of the control group.
• the data is also expressed as the ratio of the tumor volume quadrupling time of the treated tumor over the untreated control group (TVQT/CTVQT). Increasing values of this ratio indicate increased antitumor response.
• the arrow ( ⁇ ) in Group 3 indicates administration 30 minutes following administration of homoharringtonine.
• the results of Table 3 indicate that the antiproliferative activity of cisplatin is enhanced by the use of the chemopotentiator, homoharringtonine in that a more than additive effect was observed when both compounds were used to treat the tumor bearing mice (group 3) in comparison to the use of cisplatin alone (group 4) or homoharringtonine alone (group 2).
• the RIF- 1 murine fibrosarcoma tumor model was used to evaluate the antitumor activity of homoharringtonine, alone and in combination with various antiproliferative agents.
• the antiproliferative agents used include those that affect nucleic acid (e.g., DNA) integrity (e.g., cisplatin, cytarabine, camptothecin, etoposide, 5-fluorouracil, or amonafide), agents that affect structural proteins (e.g., paclitaxel, vinblastine, or colchicine) or cytoplasmic enzymes (e.g., geni stein).
• Homoharringtonine (HHT-NCI) was obtained from NCI as a powder. Homoharringtonine (HHT-Clin) was obtained from Hangzhou Minsheng Pharmaceutical Group (Hangzhou,
• Cisplatin for Injection USP
• Cisplatin for Injection USP
• Paclitaxel was obtained from Bristol Myers Squibb Co. (Princeton, NJ), Lot No.
• Camptothecin was obtained from Boehringer-Ingelheim, Lot No.142088, as a powder.
• Vinblastine was obtained from Bedford Labs (Bedford, OH), Lot No.112647, as a lypholized powder.
• Etoposide was obtained from Pharmacia (Kalamazoo, MI), Lot No. ETA013, exp.
• 5-Fluorouracil was obtained from Pharmacia (Kalamazoo, MI), Lot No.FFA191, exp. 7/00, as a liquid prediluted to 50 mg/mL.
• Amonafide was obtained from Penta Biotech (Union City, CA), Lot No.039-01, as a powder.
• Colchicine was obtained from Sigma (St. Louis, MO), Lot No.55H0685, as a powder.
• Genistein was obtained from ChemCon GmbH (Freburg i. Br.), Lot No.CC-6700-26, as a powder.
• DMSO was obtained from Sigma (St. Louis, MO), Lot No.80K3695 0.9% Sodium Chloride for Injection, USP (saline) was manufactured by Abbott Laboratories (Lot No. 55- 199-DK). Sterile Water for Injection, USP (WFI) was manufactured by Lyphomed, Inc. (Lot
• Test preparations (treatment groups) are summarized in Table 4.
• HHT-NCI was weighed into vials and dissolved in DMSO at the stated concentrations.
• paclitaxel prediluted in Cremaphor/EL and dehydrated alcohol to 6 mg/mL was further diluted to 3.3 mg/mL with WFI.
• Formulations 7 and 8 were prepared by further diluting HHT-Clin to the stated concentrations with WFI.
• Formulation 9 was undiluted HHT-Clin, used as received.
• Formulation 10 was prepared by adding 1 mL of WFI to 100 mg of cytarabine as a lypholized powder.
• Formulation 1 1 was prepared by adding DMSO to camptothecin at a concentration of 1 mg/mL.
• Formulation 12 was made by adding 0.9% Sodium Chloride for Injection to a vial of 10 mg of vinblastine lypholized powder.
• Formulations 13-17 were prepared by diluting the appropriate amount of each test agent into saline (13- 2.5 mg/mL etoposide, 14- 7.5 mg/mL 5-fluorouracil, 15- 7.5 mg/mL amonafide, 16- 2.5 mg/mL colchicine, 17- 3.75 mg/mL 5-fluorouracil).
• Formulation 18 was prepared by diluting 15 mg of genistein in 1 mL of DMSO.
• mice Female C3H mice (Charles River Laboratories, Holister, CA), approximately 3 months old, were used for the study. The average body weight was approximately 25 g. Animals were maintained in isolator cages on a 12-hour light-and-dark cycle. Food and water were available ad libitum.
• the R F-1 murine fibrosarcoma cell line was maintained in in vitro culture (Waymouth medium supplemented with 20% fetal bovine serum) at 37° C in a humidified 5 % CO 2 incubator.
• Log-phase RIF-1 cells were trypsinized and harvested from cell culture flasks to yield a concentration of 4 x 10 6 cells/mL, then injected intradermally in a volume of 50 ⁇ L (equivalent to 2 x 10 5 cells per injection) into both flanks of each mouse.
• tumors reached approximately 100 mm 3 in size, the animals were randomized to different treatment groups.
• Treatment groups are summarized in Table 4. Four to five animals were assigned to each treatment group. The intraperitoneal injection volume was 100 ⁇ L. Intratumoral injections (50 ⁇ L) were made into one of the two tumors on each animal with the contralateral tumor serving as an untreated control. The oral administration volume was 100 ⁇ L. Combination treatments using two test agents were administered as two separate injections, with the second one following the first either immediately or after 30 minutes.
• Tumors were measured three times weekly for up to 22 days with Vernier calipers. Tumor volume (cubic millimeters, mm 3 ) was calculated according to the formula:
• V ⁇ / 6 x Di x D 2 x D 3 in which D ⁇ -3 are perpendicular diameters measured in millimeters (mm).
• Tumor volume quadrupling time defined as the time required for a tumor to grow to four times its initial volume (at the time of treatment), was used as a study endpoint.
• Antitumor activity or modulation of tumor growth (as measured by delayed tumor growth, i.e. increases in TVQT values) by homoharringtonine administered as a single agent or in combination with other chemotherapeutics is presented in Table 5.
• Homoharringtonine from Hangzhou Minsheng Pharmaceutical Group (Hangzhou, China), formulated in sterile water at either 2 mg/Kg or 4 mg/Kg was used for the remainder of the combination studies.
• homoharringtonine had an average TVQT of 10.4 days in E026 while the untreated controls quadrupled in 7.4 days.
• homoharringtonine at 4 mg/Kg had an average TVQT of 8.5 days.
• Administration of homoharringtonine (4 mg/Kg) in combination with 5-fluorouracil (30 mg/Kg) resulted in a TVQT of 17.9 days versus 13.6 days for 5-fluorouracil, alone.
• Combination administration of homoharringtonine (4 mg/Kg) and vinblastine (2 mg/Kg) yielded a TVQT of 10.9 days versus 8.6 days for vinblastine, alone.
• Combination administration of homoharringtonine (4 mg/Kg) and cisplatin (4 mg/Kg) or amonafide (30 mg/Kg) yielded TVQT's of 10.4 and 10.2 days, respectively, versus 9.9 and
• genistein (60 mg/Kg) in combination with homoharringtonine (4 mg/Kg) had a TVQT of 9.2 days, which was greater than that of genistein, alone (7.1 days).
• mice There were animal deaths in some groups that were recorded as follows. Three of four mice died after treatment of homoharringtonine obtained from NCI and formulated in DMSO at
• intraperitoneal administration of homoharringtonine had antitumor activity, i.e. modulated tumor growth, in the RIF-1 murine fibrosarcoma tumor model.
• Intraperitoneal administration of homoharringtonine in combination with cisplatin, cytarabine, camptothecin, vinblastine, etoposide, 5-fluorouracil, amonafide, colchicine and genistein had antitumor activity levels greater than homoharringtonine alone, or the individual test agents.
• the best combinatorial activity used 5-fluorouracil, amonafide and vinblastine.
• Homoharringtonine in combination with paclitaxel had antitumor activity less than homoharringtonine alone.
• Homoharringtonine obtained from NCI and formulated in DMSO showed some lethal toxicity while homoharringtonine obtained from Hangzhou Minsheng Pharmaceutical Group (Hangzhou, China) and formulated in sterile water for use in humans did not show lethal toxicity at the doses used.

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