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^R○ 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. Plain language summary: What is this article about/what is the aim of the research?: Spinal muscular atrophy (SMA) is an inherited disease affecting mainly infants and children, but it can also present in adults. This condition damages nerve cells and muscles that control key activities, such as sitting, walking, speaking, swallowing and breathing. Nusinersen was the first drug approved in the US to help manage SMA. It is administered by injection with a thin needle into a space in the lower back, below the end of the spinal cord, through a medical procedure known as a “lumbar puncture”. There is very little information on the medical management for people with SMA receiving nusinersen. Using insurance claims processed in the US, this study assessed trends in hospital stays, in emergency department (ED) visits and in related medical costs before and after nusinersen use. What were the results?: Comparing the 12 months before nusinersen treatment with the 12 months following treatment, the number of hospital stays was 41% lower for children and 67% lower for adults after treatment. The average cost per person associated with hospital stays was 63% lower for children and 79% lower for adults. The number of days spent at the hospital was also reduced for all ages following nusinersen treatment. The number of ED visits and the resulting costs were 8% and 35% lower, respectively, for the overall cohort. What do these results mean?: Overall, nusinersen treatment lessens the burden of disease among people with SMA in the US by lowering the rate of hospital stays and ED visits, and by reducing associated costs.