A Study of Lenalidomide Maintenance for High-risk Patients With CLL Following First-line Therapy

CLLM1 is a phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study that compares the efficacy and safety of oral lenalidomide maintenance therapy to that of placebo maintenance therapy in high-risk subjects with Chronic Lymphocytic Leukemia (CLL) who have achieved at least a partial response (PR) and either: * MRD levels of ≥ 10-2 or * MRD levels of ≥ 10-4 - \< 10-2 combined with at least one of the following factors: * an unmutated IGHV-status * 17p-deletion or * TP53 mutation after first line therapy with FCR, FR, BR or FC (in case of of contraindications to receive Rituximab).