Hypoxic cell sensitizer

Hypoxic cell sensitizer, misonidazole, was given to 106 patients on the dose regimens of once, twice and 5 times a week with a fractional dosage ranging from 0.3 to 2.0 g/m2 of body surface in a Phase I clinical pharmacology and toxicology trial. Mean plasma levels, measured by HPLC method, were 44 μg/ml at a dosage of 1.0 g/m2 and 81 μg/ml at 2.0 g/m2 4 hours after oral administration, in which levels considerable sensitization could be expected. Various adverse reactions were observed in about 1/3 of the patients, however the drug can be used with minimal side effects, providing the total dose under 10.0 g/m2 and fractional dosage under 1.5 g/m2 once a week, 1.0 g/m2 twice a week and 0.5 g/m2 time a week in Japanese. Although the clinical trial to determine the sensitizing effect is under way at present, most of the experimenters feel that misonidazole is a promising sensitizer. Further prospects of hypoxic cell sensitizer, such as SR-2508 and combined use with hyperthermia, were also discussed. (author)