Efficacy and safety of bortezomib, thalidomide, and lenalidomide in multiple myeloma: An overview of systematic reviews with meta-analyses

This overview summarizes evidence for the efficacy and safety of bortezomib, thalidomide, and lenalidomide in patients with multiple myeloma. We searched the Medline, Scopus, and LILACS databases through August 2016, including systematic reviews with meta-analyses of randomized controlled trials assessing the efficacy and/or safety of bortezomib, thalidomide, or lenalidomide in patients with multiple myeloma. Two authors performed study selection, data extraction, and quality assessment using AMSTAR and GRADE instruments. Twenty-nine studies satisfied the inclusion criteria. All three drugs significantly improved overall response and progression-free survival; however, only bortezomib showed significantly greater overall survival compared with the control arm (induction therapy, continuous therapy, or at any phase of treatment). The main concerns on adverse events were thrombosis/embolism events, peripheral neuropathy, and second primary malignancies. The most common problems detected in systematic reviews were non-registration of the study protocol and conflicts of interest not clearly acknowledged. Future research should adhere to quality assessment tools so that best evidence can be used in decision-making. Protocol PROSPERO registration number: CRD42016036062.