Continued benefit of nusinersen initiated in the presymptomatic stage of spinal muscular atrophy: 5-year update of the NURTURE study.

INTRODUCTION/AIMS: NURTURE (NCT02386553) is an open-label study of nusinersen in children (two SMN2 copies, n = 15; three SMN2 copies, n = 10) who initiated treatment in the presymptomatic stage of spinal muscular atrophy (SMA). A prior analysis after ~3 y showed benefits on survival, respiratory outcomes, motor milestone achievement, and a favorable safety profile. An additional 2 y of follow-up (data cut: February 15, 2021) are reported. METHODS: The primary endpoint is time to death or respiratory intervention (≥6 h/day continuously for ≥7 days or tracheostomy). Secondary outcomes include overall survival, motor function, and safety. RESULTS: Median age of children was 4.9 (3.8-5.5) y at last visit. No children have discontinued the study or treatment. All were alive. No additional children utilized respiratory intervention (defined per primary endpoint) since the prior data cut. Children with three SMN2 copies achieved all World Health Organization (WHO) motor milestones, with all but one milestone in one child within normal developmental timeframes. All 15 children with two SMN2 copies achieved sitting without support, 14/15 walking with assistance, and 13/15 walking alone. Mean Hammersmith Functional Motor Scale Expanded total scores showed continued improvement. Subgroups with two SMN2 copies, minimum baseline compound muscle action potential amplitude ≥2 mV, and no baseline areflexia had better motor and nonmotor outcomes versus all children with two SMN2 copies. DISCUSSION: These results demonstrate the value of early treatment, durability of treatment effect, and favorable safety profile after ~5 y of nusinersen treatment. Inclusion/exclusion criteria and baseline characteristics should be considered when interpreting presymptomatic SMA trial data.

Effectiveness of Nusinersen in Adolescents and Adults with Spinal Muscular Atrophy: Systematic Review and Meta-analysis.

INTRODUCTION: Nusinersen clinical trials have limited data on adolescents and adults with 5q-associated spinal muscular atrophy (SMA). We conducted a systematic literature review (SLR) and meta-analysis to assess effectiveness of nusinersen in adolescents and adults with SMA in clinical practice. METHODS: Our search included papers published 12/23/2016 through 07/01/2022 with ≥ 5 individuals ≥ 13 years of age and with ≥ 6 months' data on ≥ 1 selected motor function outcomes [Hammersmith Functional Motor Scale-Expanded (HFMSE), Revised Upper Limb Module (RULM), and Six-Minute Walk Test (6MWT)]. For meta-analysis, effect sizes were pooled using random-effects models. To understand treatment effects by disease severity, subgroup meta-analysis by SMA type and ambulatory status was conducted. RESULTS: Fourteen publications including 539 patients followed up to 24 months met inclusion criteria for the SLR. Patients were age 13-72 years and most (99%) had SMA Type II or III. Modest improvement or stability in motor function was consistently observed at the group level. Significant mean increases from baseline were observed in HFMSE [2.3 points (95% CI 1.3-3.3)] with 32.1% (21.7-44.6) of patients demonstrating a clinically meaningful increase (≥ 3 points) at 18 months. Significant increases in RULM were consistently found, with a mean increase of 1.1 points (0.7-1.4) and 38.3% (30.3-47.1) showing a clinically meaningful improvement (≥ 2 points) at 14 months. Among ambulatory patients, there was a significant increase in mean 6MWT distance of 25.0 m (8.9-41.2) with 50.9% (33.4-68.2) demonstrating a clinically meaningful improvement (≥ 30 m) at 14 months. The increases in HFMSE were greater for less severely affected patients, whereas more severely affected patients showed greater improvement in RULM. CONCLUSIONS: Findings provide consolidated evidence that nusinersen is effective in improving or stabilizing motor function in many adolescents and adults with a broad spectrum of SMA.

Motor neurons are specialized cells in the brain and spinal cord that control the function of muscles. People with spinal muscular atrophy (SMA) do not make enough survival motor neuron (SMN) protein, which motor neurons need to function. As a result, people with SMA experience decreased muscle function that gets worse over time. Nusinersen is a drug that increases the amount of SMN protein made in the brain and spinal cord. However, most clinical trials of nusinersen have been in infants and children with SMA. Less is known about the effects of nusinersen in teenagers and adults with SMA who may have less severe but still progressive forms of the disease. In this manuscript, we first conducted a thorough review and analysis of research published by investigators who treated teenagers and adults with nusinersen for up to 24 months. We then used an additional analysis, called a meta-analysis, that allowed us to combine the information from several articles, so that we could better understand whether nusinersen helped these patients. We looked at 3 tests that investigators used to see how nusinersen affected patients' motor function. The Hammersmith Functional Motor Scale­Expanded (HFMSE) assesses upper and lower limb motor function; the Revised Upper Limb Module (RULM) evaluates upper limb function; and the Six-Minute Walk Test (6MWT) measures the maximum distance a person can walk in 6 minutes. Our study showed that nusinersen can improve motor function or prevent motor function from getting worse in many teenagers and adults with SMA.

Evaluation of inpatient and emergency department healthcare resource utilization and costs pre- and post-nusinersen for the treatment of spinal muscular atrophy using United States claims.

Aim: Nusinersen, administered by intrathecal injection at a dose of 12 mg, is indicated across all ages for the treatment of spinal muscular atrophy (SMA). Evidence on real-world healthcare resource use (HRU) and costs among patients taking nusinersen remains limited. This study aimed to evaluate real-world HRU and costs associated with nusinersen use through US claims databases. Patients & methods: Using the Merative™ MarketScan® Research Databases, patients with SMA receiving nusinersen were identified from commercial (January 2017 to June 2020) and Medicaid claims (January 2017 to December 2019). Those likely to have complete information on the date of nusinersen initiation and continuous enrollment 12 months pre- and post-index (first record of nusinersen treatment) were retained. Number and costs (US$ 2020) of inpatient admissions and emergency department (ED) visits, unrelated to nusinersen administration, were evaluated for 12 months pre- and post-nusinersen initiation and stratified by age: pediatric (<18 years) and adult (≥18 years). Results: Overall, 103 individuals treated with nusinersen were retained: 59 were pediatric (mean age [range]: 9 [1-17] years), and 44 were adults (30 [18-63] years). Inpatient admissions decreased by 41% for pediatrics and 67% for adults in the 12 months post-treatment versus the 12 months pre-treatment. Average inpatient admission costs per patient for the pediatric cohort decreased by 63% ($22,903 vs $8466) and by 79% ($13,997 vs $2899) for the adult cohort when comparing the 12 months pre-index with the 12 months post-index period. Total ED visits and ED visit costs decreased by 8% and 35%, respectively, for the overall cohort over the 12-month period pre- and post-index. Conclusion: Using US claims databases, nusinersen treatment in pediatric and adult patients was associated with reductions in HRU and costs over a 12-month period post-treatment initiation relative to the pre-treatment period.