ASH 2020 | HORIZON subgroup analyses: melfufen and dexamethasone in R/R MM

Maria-Victoria Mateos, MD, PhD, University of Salamanca, Salamanca, Spain, discusses the findings of key subgroup analyses conducted as part of the pivotal HORIZON study (NCT02963493) of melphalan flufenamide (melflufen) plus dexamethasone (dex) in relapsed/refractory multiple myeloma patients. Melflufen is a novel peptide-drug conjugate that targets aminopeptidases, allowing delivery of alkylating agents to myeloma cells. In the overall relapsed/refractory population, melflufen plus dex showed significant efficacy, so subgroup analyses were carried out to further characterize the population in which the combination is of benefit. One such analysis compared patient with high-risk cytogenetic abnormalities to those without, and found that melflufen plus dex was efficacious in those with high-risk cytogenetics, with a safety profile comparable to the overall population. Patients refractory to alkylator therapy were also looked at in isolation, and the results showed that there was a clinical benefit in these patients. Myeloma patients with extramedullary disease were the third subgroup analyzed, a population associated with an especially poor prognosis. Melflufen plus dex was efficacious in these patients, with promising survival outcomes in responders. This interview took place during the 62nd American Society of Hematology (ASH) Annual Meeting and Exposition, 2020.