Longitudinal Dosing Patterns and Treatment Costs Among Patients with Spinal Muscular Atrophy Initiating Nusinersen...

Area of Science:

• Neurology
• Pharmacoeconomics
• Health Services Research

Background:

• Spinal muscular atrophy (SMA) is a severe neuromuscular disorder with significant morbidity and healthcare costs.
• While disease-modifying therapies have improved outcomes, their long-term economic impact remains understudied.
• Understanding the real-world costs of chronic SMA treatments is crucial for informed therapeutic decisions.

Purpose of the Study:

• To evaluate the real-world, long-term treatment costs of nusinersen and risdiplam in patients with SMA.
• To assess drug acquisition and administration costs associated with these chronic SMA therapies.
• To inform healthcare planning and therapeutic choice by providing economic evidence.

Main Methods:

• Retrospective cohort study using the Komodo Health Research Database (2016-2024).
• Included patients with SMA aged ≥2 years initiating nusinersen or risdiplam, followed up to 5 years.
• Assessed annual dosing patterns and drug costs (2024 USD) by age group and scoliosis status.

Main Results:

• Median follow-up was 5.5 years for nusinersen and 1.1 years for risdiplam.
• Persistence declined over time: 39.5% of nusinersen patients and 63.7% of risdiplam patients remained on therapy at years 5 and 4, respectively.
• Annualized nusinersen costs ranged from $438,788-$548,608; risdiplam costs ranged from $143,331-$289,340, with costs similar across subgroups.

Conclusions:

• Both nusinersen and risdiplam demonstrated declining persistence over time.
• High long-term costs were observed for patients remaining on index therapy for both treatments.
• These findings underscore the substantial ongoing financial burden of chronic SMA therapies and the need for real-world economic data.