Onasemnogene Abeparvovec for Treating Pre-symptomatic Spinal Muscular Atrophy: An External Assessment Group Perspective of the Partial Review of NICE Highly Specialised Technology Evaluation 15

As part of the National Institute for Health and Care Excellence (NICE) highly specialised technology (HST) evaluation programme, Novartis submitted evidence to support the use of onasemnogene abeparvovec as a treatment option for patients with pre-symptomatic 5q spinal muscular atrophy (SMA) with a bi-allelic mutation in the survival of motor neuron (SMN) 1 gene and up to three copies of the SMN2 gene. The Liverpool Reviews and Implementation Group at the University of Liverpool was commissioned to act as the External Assessment Group (EAG). This article summarises the EAG’s review of the evidence submitted by the company and provides an overview of the NICE Evaluation Committee’s final decision, published in April 2023. The primary source of evidence for this evaluation was the SPR1NT trial, a single-arm trial including 29 babies. The EAG and committee considered that the SPR1NT trial results suggested that onasemnogene abeparvovec is effective in treating pre-symptomatic SMA; however, long-term efficacy data were unavailable and efficacy in babies aged over 6 weeks remained uncertain. Cost-effectiveness analyses conducted by the company and the EAG (using a discounted price for onasemnogene abeparvovec) explored various assumptions; all analyses generated incremental cost-effectiveness ratios (ICERs) that were less than £100,000 per quality-adjusted life-year (QALY) gained. The committee recommended onasemnogene abeparvovec as an option for treating pre-symptomatic 5q SMA with a bi-allelic mutation in the SMN1 gene and up to three copies of the SMN2 gene in babies aged ≤ 12 months only if the company provides it according to the commercial arrangement (i.e. simple discount patient access scheme).