Radioactive antitumor agent

Patent metadata

Field	Value
Publication number	US-12533427-B2
Application number	US-201816758081-A
Country	US
Kind code	B2
Filing date	Oct 26, 2018
Priority date	Nov 1, 2017
Publication date	Jan 27, 2026
Grant date	Jan 27, 2026

Abstract

This radioactive antitumor agent comprises a radioactive dithiosemicarbazone-copper complex as an active ingredient, and is characterized by being used in such a way that the radioactive dithiosemicarbazone-copper complex is administered multiple times to an organism requiring tumor treatment, at a radioactive dose that avoids dose-limiting toxicity, as determined on the basis of hematological parameters. The multiple administration preferably consists of intermittent administration at time intervals allowing the hematological parameters to return to a normal range.

First claim

The invention claimed is:

1 . A method of treating a tumor, which comprises performing multiple administration, at a predetermined time interval, of a radioactive antitumor agent comprising a radioactive dithiosemicarbazone-copper complex as an active ingredient to a living body in need of internal radiotherapy of the tumor at a radioactive dose that (1) effectively kills tumor cells/tissues as determined on the basis of tumor growth inhibition and survival prolongation, and (2) avoids dose-limiting toxicity as determined on the basis of a hematological parameter selected from the group consisting of white blood cell count, red blood cell count and platelet count,
wherein the radioactive dose is from 30 MBq/kg to 450 MBq/kg, and the radioactive dithiosemicarbazone-copper complex is represented by the following formula (1):

 wherein R 1 , R 2 , R 3 , and R 4 are each independently selected from the group consisting of a hydrogen atom, an alkyl group, and an alkoxy group, and Cu is a radioisotope of copper selected from the group consisting of 64 Cu and 67 Cu, and
wherein the tumor is a malignant brain tumor.

2 . The method according to claim 1 , wherein the radioactive dose is a radioactive dose that is from 75 MBg/kg to 300 MBg/kg and avoids statistically significant decrease in two or more kinds of blood cell counts at a significance level set to 5%.

3 . The method according to claim 1 , wherein the multiple administration consists of intermittent administration at a time interval during which the hematological parameter recovers to a normal range.

4 . The method according to claim 3 , wherein the time interval during which the hematological parameter recovers to a normal range is a time interval during which the hematological parameter recovers to be equal to the hematological parameter before administration.

5 . The method according to claim 1 , wherein the radioactive dose is from 100 MBq/kg to 200 MBq/kg.

6 . The method according to claim 1 , wherein the malignant brain tumor is malignant glioblastoma.

Assignees

• National Institutes For Quantum Science And Tech
• National Institutes For Quantum Science & Tech

Inventors

• Yoshii Yukie
• Matsumoto Hiroki

Classifications

• A61P35/00

  Antineoplastic agents · CPC title

• A61K51/0478 Primary

  complexes from non-cyclic ligands, e.g. EDTA, MAG3 · CPC title