INTRODUCTION: Lenalidomide use in nearly all induction regimens for multiple myeloma (MM) has led to the treatment of lenalidomide-refractory disease becoming one of the most important clinical questions in its treatment. Given the lack of direct comparisons of treatment regimens for lenalidomide-refractory MM, we used a systematic review to identify randomized controlled trials (RCTs) that included lenalidomide-refractory subgroup analysis.
METHODS: We performed a systematic review to identify RCTs for MM that enrolled patients with lenalidomide-refractory disease, then performed a network meta-analysis (NMA) using random effects model to compare regimens.
RESULTS: We identified 123 discrete RCTs, of which 7 reported primary outcomes for lenalidomide-refractory MM. These were linked in 2 discrete networks totaling 1698 lenalidomide-refractory patients. Network 1 compared bortezomib (bort)/dexamethasone (dex) versus other treatments, and analysis showed triplet therapy with pomalidomide (pom)/bort/dex (hazard ratios [HR] 0.65, 95% confidence interval [CI], 0.50-0.84), daratumumab (dara)/bort/dex (HR 0.36, 95% CI, 0.21-0.63), and dara/carfilzomib (carf)/dex (HR 0.38, 95% CI, 0.21-0.69) as more effective than bort/dex. Network 2 compared dex versus other treatments, and analysis showed pom/dex (HR 0.50, 95% CI, 0.40-0.62), isatuximab (isa)/pom/dex (HR 0.30, 95% CI, 0.20-0.44), and elotuzumab (elo)/pom/dex (HR 0.27, 95% CI, 0.16-0.45) as more effective than dex. Within each network, monoclonal antibody (mAb)-containing regimens had lower HRs and higher P-scores than non-mAb regimens, indicating higher likelihood of these regimens being most efficacious.
CONCLUSION: The results of our NMA demonstrated that for lenalidomide-refractory MM, triplet therapy containing mAbs are superior. There is need for further RCTs to better ascertain the best standard of care for these patients.