The Survival Impact of Lenalidomide Maintenance Therapy in Patients with Multiple Myeloma; An Analysis of Real-World Data from the Myeloma Canada Research Network Canadian Multiple Myeloma Database.

Abstract

Historically, the treatment of multiple myeloma in transplant eligible patients has included induction chemotherapy followed by autologous stem cell transplant (ASCT) and a watch and wait approach until relapse. The introduction of maintenance chemotherapy has changed the traditional observation period into active treatment time. We examined the impact of lenalidomide maintenance on survival outcomes in the front line and relapsed setting. Our population included patients treated with bortezomib based induction followed by ASCT who went on to receive lenalidomide maintenance or no maintenance. Patient data was taken from the Myeloma Canada Research Network Canadian Multiple Myeloma Database (MCRN CMM-DB) which includes data from 13 academic cancer centers across Canada.Our data demonstrates that lenalidomide maintenance is associated with improved progression free (PFS) and overall survival (OS) as well as higher rates of favourable responses. We did not observe any unanticipated adverse effects. Rates of discontinuation for reasons other than relapse were low. Analysis of relapsed patients demonstrates that lenalidomide maintenance did not results in worse second PFS (time from second line therapy to second relapse, death or last follow-up) in patients who received the drug again in second line therapy. Lenalidomide maintenance was associated with improve overall survival from time of initiation of relapse therapy. Additionally, lenalidomide maintenance did not negatively impact second PFS, OS from time of initiation of relapse therapy, and rates of favourable response when lenalidomide used again in second line treatment. Our data is the first analysis of transplant eligible patients from the MCRN CMM-DB. Our data supports the continued use of lenalidomide maintenance as standard of care following ASCT. Importantly, our data suggests that the use of lenalidomide maintenance does not negatively impact survival or response outcomes when used again in second line therapy. As such, use of or relapse on lenalidomide maintenance should not be considered an exclusion criteria for use of lenalidomide in second line therapy.