Background: This is a phase I/II study of second-line chemotherapy with paclitaxel and irinotecan in fluoropyrimidine- and platinum-pretreated patients with metastatic or recurrent gastric cancer.
Methods: Phase I part with a standard 3 + 3 dose-escalation design was conducted to define the recommended phase II dose (RP2D) using four predefined dose levels of paclitaxel and irinotecan. The efficacy of RP2D was evaluated in a phase II part.
Results: In phase I part, 12 patients were enrolled. Dose-limiting toxicity was not observed. The RP2D was established as level 4 (paclitaxel-135 mg/m(2) and irinotecan-160 mg/m(2), every 3 weeks). In phase II part, 27 patients were enrolled. Thirty patients, including three patients at dose level 4 in the phase I part, were analyzed for efficacy. There was no complete response. Partial response and stable disease were reported in four and 16 patients, respectively (response rate 13.3 %, 95 % CI 0.0-25.5 %; disease control rate 66.6 %, 95 % CI 49.0-83.0 %). The median time to progression and overall survival was 3.0 months (95 % CI 1.8-4.2) and 10.1 months (95 % CI 6.6-13.6), respectively. Grade 3/4 toxicities included neutropenia (2 patients, 7.4 %), thrombocytopenia (1, 3.7 %), neutropenic fever (1, 3.7 %), and diarrhea (1, 3.7 %). There were no treatment-related deaths.
Conclusion: The RP2D of the paclitaxel and irinotecan combination is paclitaxel (135 mg/m(2)) and irinotecan (160 mg/m(2)), every 3 weeks. This combination as a second-line treatment for advanced gastric cancer shows tolerable toxicity and modest efficacy.