An evaluation of onasemnogene abeparvovec for spinal muscular atrophy (SMN1)

Introduction Onasemnogene abeparvovec is the first systemic gene replacement therapy approved by the FDA for any inherited condition and is the second FDA-approved genetic therapy for 5q spinal muscular atrophy. Areas covered We discuss the design and preclinical development of onasemnogene abeparvovec, along with clinical trial and real-world data focusing on efficacy and safety. Expert Opinion Although onasemnogene abeparvovec is strikingly effective for the treatment of 5q SMA, it is only approved for use under the age of 2 years and there are also two other FDA-approved molecular-based treatments. Many questions remain in terms of treatment selection, possibility of dose optimization, and combinational therapies.