tirapazamine

Tirapazamine is an experimental anticancer small molecule that acts as a prodrug selectively activated under hypoxic conditions commonly found in solid tumors. Upon activation by cellular reductases in low oxygen environments, it generates cytotoxic free radicals—primarily hydroxyl and benzotriazinyl radicals—that cause DNA strand breaks and cell death. This mechanism targets hypoxic tumor cells that are typically resistant to conventional chemotherapy and radiotherapy. Tirapazamine has been investigated primarily for use in combination with other anticancer agents such as cisplatin or carboplatin to enhance their efficacy without increasing systemic toxicity. It has undergone phase III clinical trials for head and neck cancer and gynecological cancers but did not demonstrate improved overall survival when added to standard chemoradiotherapy regimens.

Other names

tirapazamine3-amino-1,2,4-benzotriazine 1,4-dioxide