The drug is a bioreductively-activated, hypoxia-selective small molecule that acts primarily in hypoxic regions of tumors, wherein tirapazamine radicals cause double-stranded DNA breaks. It was originally identified as an anticancer agent by Silicon Valley-based SRI and Stanford University researchers investigating oxygen deficiency (hypoxia) in solid tumors.
“Tirapazamine has been shown to be highly effective in experimental models, and we are interested in finding the right partner to continue clinical development of the drug,” said Edward Spack, senior director of business development for SRI Biosciences Division. “To date it has been studied in patients with head and neck, non-small cell lung, ovarian, and other cancers, with mixed results. Clinical studies are continuing, including government and investigator-sponsored trials.”
Sanofi-Aventis said in its 2006 results statement in February that it had discontinued its development of tirapazamine last year.