A Phase I Study of Napabucasin Plus Paclitaxel for Japanese Patients With Advanced/Recurrent Gastric Cancer

AIM: To report results from the first phase I study of napabucasin plus paclitaxel in Japanese patients with pre-treated unresectable/recurrent gastric cancer. PATIENTS AND METHODS: Patients received napabucasin (480 mg bid) plus paclitaxel [80 mg/m2 on days 3, 10 and 17 (cycles 1 and 2) and on days 1, 8 and 15 (cycle 3 and subsequent cycles)] until disease progression or unacceptable toxicity. Primary objectives were tolerability, safety and pharmacokinetics of napabucasin plus paclitaxel. Trial registration ID: JapicCTI-142420. RESULTS: Six patients were enrolled. Paclitaxel had a minimal effect on napabucasin pharmacokinetics and median plasma paclitaxel concentrations were similar in combination and monotherapy. No dose-limiting toxicities were observed. There were no grade 4/5 adverse events. Partial response, stable disease and progressive disease were reported in two patients each. CONCLUSION: Napabucasin plus paclitaxel was well-tolerated in Japanese patients with gastric cancer.