Consolidation treatment with lenalidomide may improve response in patients with residual disease after treatment

This study examined lenalidomide (Revlimid) as a consolidation strategy in patients with chronic lymphocytic leukemia (CLL) who have residual disease after treatment. This study reported good response improvements (in 45% of patients with residual disease). Lenalidomide may be particularly suited as a consolidation strategy after first-line treatment.

Standard therapy for CLL usually involves a combination of chemotherapies and immunotherapies. The aim of chemo-immunotherapy is to induce remission (no sign of the disease). Consolidation therapy after remission is typically administered to reduce the risk of relapse. Lenalidomide is a type of immunotherapy commonly used as a consolidation strategy. Whether lenalidomide is safe and effective for patients who have residual disease after treatment has not been fully studied.

32 CLL patients were included in this study. All patients showed evidence of minimal residual disease (MRD; small number of leukemia cancer cells that remain after treatment) in the bone marrow after chemo-immunotherapy. Consolidation therapy with lenalidomide was started after an average of 7 months. 12 patients received lenalidomide at a daily dose of 10 mg for 3 months. The remaining 20 patients received the same treatment for up to 12 months. Patients were followed for an average of 47 months.

25% of patients were in complete remission with positive MRD at the start of consolidation therapy. 75% were in partial remission with positive MRD. 41% of patients received consolidation therapy after first-line treatment. The remaining patients (59%) had undergone 2 or more prior lines of treatment.

Response improvement was observed in 13 patients (45%). Four of the 8 patients with very good partial remission improved to complete remission. Of these, 2 tested negative for MRD. Seven of the 15 patients with medium partial remission improved to complete remission. Of these, 1 was negative for MRD.

20 patients (69%) progressed during the study period. The average time to disease progression for the whole group was 30 months. It was 39 months for patients who showed response improvement with the consolidation therapy. Patients who received consolidation therapy after 2 or more lines of prior treatment had a progression-free survival of 29 months. This was significantly shorter compared to patients who received it after first-line treatment (43 months).

5 patients (16%) discontinued treatment because of side effects. 16 patients showed severely low neutrophil counts (a type of white blood cell). All cases were resolved with dose reduction or gradual treatment discontinuation. 

The authors concluded that lenalidomide is a safe and effective consolidation strategy for CLL patients treated with chemo-immunotherapy.

Larger studies are needed to confirm these results.