Wang M, et al. - Researchers performed the observational MCL-004 study to evaluate outcomes in patients with relapsed/refractory mantle cell lymphoma who received lenalidomide-based therapy after ibrutinib failure or intolerance. In patients with relapsed/refractory mantle cell lymphoma who previously failed ibrutinib therapy, lenalidomide-based treatment demonstrated clinical activity, with no unexpected toxicities.

Methods

• Based on the 2007 International Working Group criteria, investigator-assessed overall response rate was examined primarily.

Results

• In total 58 patients were enrolled (median age, 71 years; range, 50-89); 13 received lenalidomide monotherapy, 11 lenalidomide plus rituximab, and 34 lenalidomide plus other treatment.
• Three or more prior therapies (median 4; range, 1-13) were observed in majority of the patients (88%) .
• Lenalidomide was initiated after a median period of 1.3 weeks from last dose of ibrutinib (range, 0.1-21.7); 45% of patients had partial responses or better to prior ibrutinib.
• Ibrutinib discontinuation was performed primarily due to lack of efficacy (88%) and ibrutinib toxicity (9%).
• 17 patients responded (8 complete responses, 9 partial responses) after a median of two cycles (range, 0-11) of lenalidomide-based treatment; overall response rate was 29% (95% confidence interval, 18-43%) and median duration of response was 20 weeks (95% confidence interval, 2.9 to not available).
• Researchers observed an overall similar response rate to lenalidomide-based therapy for patients with relapsed/progressive disease after previous response to ibrutinib (i.e., ≥PR) vs ibrutinib-refractory (i.e., ≤SD) patients (30 vs 32%, respectively).
• After lenalidomide-containing therapy, the most common all-grade treatment-emergent adverse events (n = 58) were fatigue (38%) and cough, dizziness, dyspnea, nausea, and peripheral edema (19% each).
• At data cutoff, death of 28 patients, primarily due to mantle cell lymphoma, was reported.