A phase I, open-label, dose-escalation study of amrubicin in combination with lenalidomide and weekly dexamethasone in previously treated adults with relapsed or refractory multiple myeloma

This phase 1 study investigated the safety of the anthracycline amrubicin combined with lenalidomide and dexamethasone in adults with relapsed or refractory multiple myeloma. A standard 3 + 3 design was used. Patients received intravenous amrubicin 40–80 mg/m² on day one, lenalidomide 15 mg orally on days 1–14, and dexamethasone 40 mg orally weekly on 21 day cycles. 14 patients were enrolled, and completed a median of three cycles. The maximum tolerated dose was not reached. One patient experienced dose limiting toxicity of dizziness and diarrhea. The most frequent non-hematologic toxicity was infection (79%). Serious adverse events included cord compression and sepsis. Three patients (21%) had a partial response or better, and seven (50%) had stable disease. The median duration of response was 4.4 months, and the median progression-free survival was 3 months. Amrubicin combined with lenalidomide and dexamethasone, was safe and demonstrated clinical activity in relapsed or refractory multiple myeloma.