Melflufen for triple-class refractory multiple myeloma | Final topline results from the phase II HORIZON study released

The final topline results from the phase II HORIZON (NCT02963493) study have recently been released. The trial investigated the efficacy and safety of melphalan flufenamide (melflufen) plus dexamethasone for the treatment of patients with relapsed or refractory multiple myeloma (RRMM).¹ The results demonstrate favorable efficacy and safety profiles for melflufen in patients with RRMM, including those with triple-class refractory- and extramedullary disease (Table 1).The data from this study are set to form the foundations of a new drug application (NDA) for accelerated approval to the U.S. Food & Drug Administration (FDA).¹

Table 1. Primary endpoint results of the HORIZON study

EMD, extramedullary disease; IRC, independent review committee; ITT, intention to treat; ORR, overall response rate *Two unconfirmed responders on January 14 have later been confirmed.
Primary endpoint, %	Investigator assessed (January 14)	IRC (January 14)	Including unconfirmed responses at time of data cut-off *
ORR in the ITT population (n = 157)	29	30	31 (investigator and IRC)
ORR in triple-class refractory patients (n = 119)	26	26	27
ORR in patients with EMD (n = 55)	24	27	NA

 A previous analysis of the HORIZON study was presented by Paul Richardson at the 24^th Congress of the European Hematology Association (EHA). Read the MM Hub coverage here.