Dose escalation study of tezacitabine in combination with cisplatin in patients with advanced cancer

The authors performed a dose escalation study of cisplatin and the novel deoxycytidine analog, tezacitabine, to determine the maximum tolerated dose of the combination.

Twenty-three patients with advanced cancer and good performance status were accrued to 3 dose levels of tezacitabine (150-270 mg/m(2)) and cisplatin (50 mg/m(2)). Using a 28-day treatment cycle, both drugs were administered on Days 1 and 15.

Hematologic toxicity was the most frequently observed side effect and was dose limiting. Grade 3 or 4 neutropenia and thrombocytopenia complicated 75% and 31% of all cycles, respectively. Nonhematologic toxicities were mild. Among 18 evaluable patients, 2 with upper gastrointestinal tract tumors achieved partial responses and 4 had stable disease.

Based on dose-limiting neutropenia and thrombocytopenia at the highest dose level, the recommended Phase II doses are 200 mg/m(2) of tezacitabine and 50 mg/m(2) of cisplatin.