A Phase I Study of Lenalidomide plus Chemotherapy with Mitoxantrone Etoposide and Cytarabine for the Reinduction of Patients with Acute Myeloid Leukemia

摘要

Patients with relapsed AML have a poor prognosis and limited responses to standard chemotherapy. Lenalidomide is an immunomodulatory drug that may modulate anti-tumor immunity. We performed a study to evaluate the safety and tolerability of lenalidomide with mitoxantrone, etoposide and cytarabine (MEC) in relapsed/refractory AML. Adult patients with relapsed/refractory AML were eligible for this phase I dose-escalation study. We enrolled 35 patients using a ‘3+3’ design, with a 10 patient expansion cohort at the maximum tolerated dose (MTD). Lenalidomide was initially given days 1–14 and MEC days 4–8; due to delayed count recovery, the protocol was amended to administer lenalidomide days 1–10. The dose of lenalidomide was then escalated starting at 5 mg/d (5–10-25–50). The primary objective was tolerability and MTD determination, with secondary outcomes including overall survival (OS). The MTD of lenalidomide combined with MEC was 50mg/d days 1–10. Among the 35 enrolled patients, 12 achieved complete remission (CR) (34%, 90%CI 21–50%); 30-day mortality was 6% and 60-day mortality 13%. The median OS for all patients was 11.5 months. Among 17 patients treated at the MTD, 7 attained CR (41%); the median OS was not reached while 12-month OS was 61%. Following therapy with MEC and lenalidomide, patient CD4+ and CD8+ T-cells demonstrated increased inflammatory responses to autologous tumor lysate. The combination of MEC and lenalidomide is tolerable with an RP2D of lenalidomide 50mg/d days 1–10, yielding encouraging response rates. Further studies are planned to explore the potential immunomodulatory effect of lenalidomide and MEC.