An updated analysis of the phase 1 trial of MCARH109 (GPRC5D-CAR T cell therapy for MM, NCT04555551) showed no new serious adverse events at a median follow-up of 37 months, with 71% of patients responding, a median response duration of 8.6 months, a 3-year overall survival estimate of 59%, and an association between an activated T-cell phenotype at apheresis and response, while possible GPRC5D loss was observed in 60% of patients at relapse (41). The gene discussed is GPRC5D; the disease is Miyoshi myopathy.