Maintenance low-dose fixed duration lenalidomide and rituximab following bendamustine and rituximab induction in previously untreated chronic lymphocytic leukemia and small lymphocytic lymphoma.

Lenalidomide (LEN) and rituximab (RTX) have independently improved progression-free survival (PFS) in CLL, leading to interest in use of LEN + RTX (R2) following induction chemoimmunotherapy. Patients with previously untreated CLL received bendamustine + RTX (BR) for 6 cycles, then 24 cycles of R2. LEN dosing was 5-10 mg daily; RTX was given odd cycles (12 doses). The primary endpoint is PFS; secondary endpoints are response and overall survival. Thirty-six patients enrolled, median age 64.5 years. Twenty-nine received R2; 12 completed a full course R2 (33.3%), 5 completed R2 with premature discontinuation of LEN. Dose reductions/holds were most often for neutropenia. Complete response was achieved in 33.3%. After median >4 years follow-up, 2-year and 3-year PFS were 86.1% and 69.4%. Five-year overall survival was 92.3%. R2 maintenance may improve PFS after BR induction, and a lower dose of 5 mg/day and ≤1 year of R2 may be most tolerable (NCT00974233).