Tirapazamine is a new bioreductive agent that has exhibited cytotoxic activity against advanced tumours. Current studies are investigating how this agent can be used to its maximum potential. A combination of cisplatin and tirapazamine appears to be effective in chemotherapy-naive non-small cell lung cancer (NSCLC), leading to a greater response rate than that associated with cisplatin monotherapy. However, the combination has shown little promise in platinum-resistant tumours in phase II trials to date. Data from these studies were presented at the 9th National Cancer Institute (NCI) - European Organisation for the Research and Treatment of Cancer (EORTC) joint symposium [Amsterdam, The Netherlands; March 1996].