Background: Treatment options for small cell lung cancer (SCLC) remain inadequate. Irinotecan has been tested in various combinations with platinum agents but the optimal regimen remains uncertain. We undertook a phase I trial to optimise the dose intensity of a 3-weekly irinotecan/carboplatin combination.
Methods: Twenty patients with extensive stage SCLC received intravenous carboplatin at an area under the curve (AUC) of 5 on day 1, and irinotecan in 40-70 mg/m2 dose levels on days 1 and 8, every 21 days, for up to 6 cycles.
Results: Dose-limiting toxicity occurred in 1 patient at the 50 mg/m2 irinotecan level (grade 3 diarrhoea) and in 2 patients at 70 mg/m2 (grade 5 neutropenic sepsis; combined grade 4 febrile neutropenia, grade 4 diarrhoea and grade 3 thrombosis). Toxicity patterns were consistent with the expected profile for this combination. The objective response rate was 75% and the median survival was 9.3 months (95% confidence interval 7.5-11.2).
Conclusion: Irinotecan 60 mg/m2 on days 1 and 8 combined with carboplatin AUC 5 every 21 days is recommended for phase II evaluation. This regimen has clinical activity, acceptable toxicity and greater dose intensity over those currently tested in phase III trials.
Copyright © 2012 S. Karger AG, Basel.