Clinical outcome and efficacy of nusinersen in Korean adult patients with 5q spinal muscular atrophy: Nationwide multicenter retrospective study

Abstract

IntroductionSpinal muscular atrophy (SMA) is a genetic motor neuron disorder, marked by progressive skeletal and respiratory muscle weakness. The recent approval of nusinersen has transformed the therapeutic landscape for SMA patients, particularly children. However, as randomized controlled studies and long-term real-world evidence in adults remain limited, this study focuses on the efficacy of nusinersen in adults with SMA in South Korea.MethodClinical data were retrospectively collected from adult patients who began nusinersen in tertiary neurology centers across the country, with 19 patients eventually being enrolled.ResultsThe results showed that Hammersmith Functional Motor Scale-Expanded scores improved significantly by 2.28 (p = 0.0002) in all patients after 12 months. Following the dropout of 4 patients who failed to meet insurance reimburse criteria, improvements of 4.55 (p = 0.0010) and 6.57 (p = 0.0156) points were noted in the remaining 15 patients after 24 and 36 months, respectively. At these time points, 40%, 82%, and 86% of patients, respectively, accomplished clinically meaningful improvements. Type 2 SMA patients exhibited a faster drug response compared to type 3a patients. Out of 176 injections, seven adverse events were reported, including post-puncture headache and injection site pain.ConclusionsOur multicenter real-world study demonstrates the sustained efficacy and manageable safety profile of nusinersen in adult SMA patients, supporting the long-term use in this population.