Yesterdays results presented at ASH 2014 provides the first demonstrated feasibility and efficacy of a chemotherapy-free, biologic approach using lenalidomide and rituximab as an initial therapy for mantle cell lymphoma (MCL). These findings present an important chemotherapy-free alternative initial treatment for MCL, as current conventional upfront chemoimmunotherapies are generally not curative.
During this multi-center phase II study patients were administered lenalidomide at 20 mg in days 1-21 of a 28-day cycle for a total of 12 cycles, with doses escalated to 25 mg when tolerated. Rituximab was administered weekly x 4 during first cycle and then once every other cycle for a total of 9 doses. The induction phase was followed by a maintenance phase, which at the 13th cycle, lenalidomide was administered at 15 mg on days 1-21 of a 28 day cycle, while rituximab maintenance was employed once every other cycle until disease progression.
Of the 38 patients with previously untreated MCL the median age was 65 years (range 42-86), with a male to female ratio of 2.5:1. Treatment was generally well tolerated with mild to moderate side effects. The overall response rate in patients was 84.2%, complete response rate was over 50%, with median time to objective response being 2.8 months. The median progression-free survival has not been reached, and the 2 year progression free survival rate is estimated to be 83.9%.
This study demonstrated that a high proportion of MCL patients can achieve durable remissions while maintaining a high quality of life. The data gathered from this trial justifies further evaluations of the lenalidomide and rituximab regimen both alone and in combination with other treatment approaches to MCL.
New Developments in Lymphoma 