Decitabine Is Effective and Safe In Patients with Chronic Myelomonocytic Leukemia

Chronic myelomonocytic leukemia (CMML) is a rare yet indolent disease. The median survival duration in CMML is 12 to 18 months and patients with poor prognostic features do even worse, with median survival time ranging 3 to 6 months. Activity with decitabine in CMML has been previously reported. We sought to analyze the clinical experience of 17 adults with a diagnosis of CMML treated on two decitabine studies.

A subset of patients with CMML from a pivotal phase III 3-day dosing and an open-label trial of 5-day dosing were identified and reviewed to determine the overall response rate (ORR, based on IWG 2006 criteria), duration of response, time to response, and overall survival (OS).

A total of 17 patients with CMML were included in this review. Mean age at diagnosis was 71 years (range, 47 to 81 years) with a mean time from diagnosis of 406.4 days. The majority of CMML patients had de novo (94.1%), good risk cytogenetics (58.8%) with an IPSS classification of Intermediate-1 (64.7%). Baseline mean white blood count (WBC), hemoglobin (HGB), and platelets (plts) were 7.5 × 10³/μ L, 14.6 g/dL and 81.9 × 10³/μ L, respectively. A larger proportion of CMML patients at baseline were plt and RBC transfusion independent. Objective response rate (ORR) was 41% [17.6% complete response (CR) and 23.5% marrowCR (mCR)]; Hematologic improvement (HI) was observed in 11.7% and stable disease in 29.4% of patients. Median survival was 391 (95% CI 239, 678) days and 2 (11.7%) patients progressed to AML. The adverse event profile was similar to observations in previous trials with myelosuppression and infectious complications.

This retrospective review of responses in CMML patients supports previous findings of decitabine experience in this population. In this analysis an overall response rate of 41.4% was achieved. Decitabine provided anti-CMML activity with an acceptable safety profile.

Jabbour:Eisai Inc.: Editorial and statistical support from Eisai Inc., Honoraria. Kantarjian:Novartis: Research Funding; Pfizer: Research Funding; Bristol Myers Squibb: Research Funding; Novartis: Consultancy. Ravandi:Eisai Inc.: Research Funding; Eisai Inc.: Honoraria. Borthakur:Eisai Inc.: Research Funding. Cortes:Novartis: Research Funding; Pfizer: Consultancy, Research Funding; Bristol Myers Squibb: Research Funding.