Phase i and pharmacologic study of weekly amrubicin in patients with refractory or relapsed lung cancer: Central Japan Lung Study Group (CJLSG) 0601 trial

Purpose To evaluate the safety and tolerability of amrubicin (AMR), determine its maximum tolerated dose (MTD), its dose-limiting toxicities (DLTs), and its recommended dose (RD), and to conduct a pharmacokinetic study of weekly AMR administrations in patients with chemotherapy-refractory or recurrent small cell or non-small cell lung cancer. Patients and methods Patients with refractory or relapsed non-small cell and small cell lung cancer after 1 or 2 regimens of chemotherapy were eligible. AMR was initiated at 45 mg/m ² weekly (repetition of dose on 1st and 8th day with a rest on day 15). The dose level was increased by 5 mg/m ² by modified Fibonacci dose escalation scheme. Results Seven patients had small cell lung cancer and 9 had non-small cell lung cancer. Fifty-four courses (median: 3, range: 1-6) were administered at 5 dose levels. At 65 mg/m ², 3 patients had DLTs as follows: 1 was grade 3 (CTCAE v3.0) in AST/ALT, 1 was grade 3 febrile neutropenia, and 1 was grade 4 neutropenia. Leukocytopenia and neutropenia were correlated with amrubicinol (AMR-OH) Cmax (P = 0.042, P = 0.047, respectively). The AUC (area under the curve of plasma concentration versus time extrapolated to concentration zero) of AMR and AMR-OH did not depend on the dose levels. Conclusion In the present phase I study of AMR administered weekly to previously treated lung cancer patients, the maximum tolerated dose and RD were 65 and 60 mg/m ², respectively. The best response rate was 15.4%, and adverse events with this schedule were tolerable.