Administration practice and adherence of nusinersen in adults with 5q-spinal muscular atrophy in China: an ambispective multicenter study

Due to nusinersen’s route of administration and dosing regimen, the spinal muscular atrophy (SMA) population and/or their caregivers need to travel to hospitals and work around physician’s schedules to receive treatment. Real-world studies with large sample sizes on administration practice and adherence rate of nusinersen are lacking, especially in non-United States settings. This study aimed to investigate the administration practice and adherence of nusinersen in Chinese adults with 5q-SMA. An ambispective, multicenter registry of adults with 5q-SMA in China provided the longitudinal data for this analysis. Nusinersen was scheduled on Day 0, 14, 28, 63, and every 4 months thereafter. Adherence rate was calculated at dose level. A dose was deemed adherent if the interval between the current and preceding dose aligned with the standard dosing regimen, allowing a grace period of ± 7 days for doses 2 through 4 and ± 28 days for all subsequent doses. A total of 177 participants receiving nusinersen with 1,329 doses were included in the study. All injections were given in inpatient setting with no ventilatory support or sedation needed. Only one injection (0.1%) was performed under general anesthesia. Almost all (n = 1,322, 99.5%) injections were given through interspinous lumbar puncture. Injections in participants with scoliosis require more imaging techniques for guiding administration compared with those in participants without scoliosis (68.3% vs. 29.1%). Ultrasound was the most commonly used guide before or during administration (674/708). The adherence rate was 92.8% (1,062/1,144). The median inter-dose intervals aligned well with dosing schedule, with 14 days for Dose 2 and 3, 35 days for Dose 4, and 120–124 days for Dose 5 to 10 as maintenance doses. Findings characterize the patterns of nusinersen administration practice, demonstrating high real-world adherence to nusinersen administration in Chinese adults with 5q-SMA. The registry was registered at clinicaltrials.gov (NCT05618379) on November 16th, 2022.