# US 8,569,324 B2 · Potentiator for radiation therapy comprising pyridine derivative as active ingredient > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,569,324 B2 - Document ID: US8569324B2 - Status: Granted - Kind: B2 - Application number: 12/978,743 - Filed: 2010-12-27 - Published: 2011-04-21 - Granted: 2013-10-29 - Earliest claimed: 2005-04-01 - Assignees: Taiho Pharmaceutical Co., Ltd. - Applicants: Masakazu Fukushima - Inventors: Masakazu Fukushima - Web page: https://patentgrep.com/patent/US8569324B2 ## CPC - C07D 213/69: Two or more oxygen atoms - A61K 41/0038: {Radiosensitizing, i.e. administration of pharmaceutical agents that enhance the effect of radiotherapy (radiotherapy per se A61N5/10)} - A61P 35/00: Antineoplastic agents - C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08) - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS ## Abstract The present invention relates to a radiotherapy enhancer that can reduce the radiation dose and adverse drug reactions when used in combination with a cancer radiotherapy. There is provided a radiotherapy enhancer comprising, as an active ingredient, a pyridine derivative represented by general formula (1): wherein R1, R2, and R4 may be the same or different from one another and represent a hydrogen atom, hydroxy group, or protected hydroxy group, excluding the case where R1, R2, and R4 are all a hydrogen atom, and R3 represents a halogen atom, amino group, carboxyl group, carbamoyl group, cyano group, nitro group, alkyl group having 1 to 6 carbon atoms, alkenyl group having 2 to 6 carbon atoms, or carbonyl group containing an alkoxy group having 1 to 6 carbon atoms). ## Claims ### Claim 1 A method of enhancing radiotherapy effects for tumor treatment, consisting of: administering to a subject in need thereof an amount, effective for enhancing radiotherapy effects, of a pyridine compound represented by the formula (1): wherein R1, R2, and R4 may be the same or different from one another and represent a hydrogen atom, hydroxy group, or protected hydroxy group, with the proviso that R1, R2, and R4 are not all a hydrogen atom, and R3 represents a halogen atom, amino group, carboxyl group, carbamoyl group, cyano group, nitro group, alkyl group having 1 to 6 carbon atoms, alkenyl group having 2 to 6 carbon atoms, or carbonyl group containing an alkoxy group having 1 to 6 carbon atoms; and irradiating said subject, thereby the effects of irradiation are enhanced. ### Claim 2 (depends on 1) The method according to claim 1, wherein R1 and R2 may be the same or different from each other and represent a hydroxy group or a protected hydroxy group, and R4 represents a hydrogen atom. ### Claim 3 (depends on 1) The method according to claim 1, wherein R1 and R4 may be the same or different from each other and represent a hydroxy group or a protected hydroxy group, and R2 represents a hydrogen atom. ### Claim 4 (depends on 1) The method according to claim 1, wherein two of R1, R2, and R4 represent a hydroxy group and the remaining group represents a hydrogen atom, and R3 represents a halogen atom or a cyano group. ### Claim 5 (depends on 1) The method according to claim 1, wherein R1 and R2 represent a hydroxy group, R3 represents a chlorine atom, and R4 represents a hydrogen atom. ### Claim 6 (depends on 1) The method according to claim 1, wherein R1 and R4 represent a hydroxy group, R3 represents a cyano group, and R2 represents a hydrogen atom. ### Claim 7 (depends on 1) The method according to claim 1, wherein said subject has a malignant tumor. ### Claim 8 (depends on 7) The method according to claim 7, wherein said malignant tumor comprises at least one tumor selected from the group consisting of head and neck cancer, esophageal cancer, gastric cancer, colorectal cancer, liver cancer, gallbladder cancer, bile duct cancer, pancreatic cancer, lung cancer, breast cancer, bladder cancer, prostate cancer, cervical cancer, brain tumor, malignant lymphoma, acute leukemia, chronic leukemia, medulloblastoma, retina retinoblastoma, neuroblastoma, Wilms' tumor, Hodgkin's disease, multiple myeloma, plasmacytoma, thymoma, basal cell cancer, squamous cancer, Ewing's tumor, thyroid cancer, ovary cancer, salivary gland cancer, teratoma, malignant melanoma, neuroglioma, renal cell carcinoma, and osteosarcoma. ### Claim 9 (depends on 7) The method according to claim 7, wherein said malignant tumor comprises at least one tumor selected from the group consisting of head and neck cancer, esophageal cancer, gastric cancer, colorectal cancer, liver cancer, lung cancer, pancreatic cancer, and breast cancer. ### Claim 10 (depends on 7) The method according to claim 7, wherein said malignant tumor comprises at least one tumor selected from the group consisting of lung cancer and pancreatic cancer. ### Claim 11 (depends on 1) The method according to claim 1, wherein said subject is irradiated with a X-ray. ### Claim 12 (depends on 1) The method according to claim 1, wherein the pyridine compound is administered in the amount of 0.05-100 mg per kg of body weight. ### Claim 13 (depends on 1) The method according to claim 1, wherein the pyridine compound is administered in the amount of 0.1-50 mg per kg of body weight.