A systematic review and meta-analysis of interventional studies of bisphosphonates and denosumab in multiple myeloma and future perspectives

Bisphosphonates (BPs) and denosumab (DENOS), due to their ability to inhibit osteoclast activity, are used to prevent skeletal complications in multiple myeloma (MM) patients. The NCBI PubMed, Web of Science, Scopus and ClinicalTrials.gov databases, were systematically searched for interventional studies, assessing the use of BP and DENOS in MM patients. Overall survival, disease progression, skeletal-related events, bone pain, osteonecrosis of the jaw (ONJ) and renal toxicity were the outcomes of interest. A total of 993 studies were retrieved and 43 were used for qualitative synthesis. Clodronate (CLOD) and zoledronic acid (ZOL) were effective in reducing skeletal complications compared to placebo. Results are mixed regarding the efficacy of pamidronate in reducing skeletal related events. ONJ rates were higher for ZOL, but under 5%, with CLOD having the safest profile. DENOS demonstrated non-inferiority to ZOL, in improving overall survival [pooled Hazard Ratio(HR) 1.02(95% CI 0.72,1.44)], progression free survival [pooled HR 0.92(95% CI 0.76,1.11)] and in reducing skeletal related events [pooled HR 1.03(95% CI 0.92,1.16)], with similar rates of ONJ and better safety profile regarding renal toxicity. Denosumab has comparable efficacy and safety with ZOL and may even replace BPs in the future, in the management of myeloma bone disease.