OBJECTIVES: SMA is a genetic neuromuscular disease. Onasemnogene abeparvovec (OA; gene therapy), nusinersen (disease-modifying therapy), and risdiplam (oral drug) are the first-in-class treatment options for SMA. This study aimed to assess the budgetary impact of introducing these treatments as a single therapy, with or without a PBMEA, for SMA types 1, 2, and 3 from the perspective of the Ministry of Health (MOH) of the Kingdom of Saudi Arabia.

METHODS: A budget impact model was developed using the available data on various model inputs (patients, treatment options, resources, and cost) collected through an explorative literature review followed by primary market research and validation by expert committees. The model was used to estimate the total cost (drug acquisition, administration, and disease management) for the best supportive care (BSC) with and without these treatments, over a 5-year period. Results were presented as the overall net budget impact of using BSC plus the treatment over BSC alone.

RESULTS: For SMA type 1, the overall net budget impact of using OA, nusinersen, or risdiplam was Saudi Riyal (SAR) 39,590,134 (156%), SAR 56,918,293 (225%), or SAR 28,373,040 (112%), without a PBMEA, while, SAR 19,575,411 (77%), SAR 5,946,301 (84%), or SAR 20,392,379 (81%), with a PBMEA. Similarly, for SMA type 2 and 3, it was SAR 12,379,218 (254%; only for type 2 patients <2 years old), SAR 265,013,008 (283%), or SAR 160,408,800 (171%), without a PBMEA, while SAR 5,693,128 (117%), SAR 23,273,924 (76%), or SAR 5,618,215 (36%), with a PBMEA.

CONCLUSIONS: This is the first analysis of first-in-class SMA treatments to estimate the budgetary impact with or without PBMEAs. Their introduction will have an impact on the MOH budget with drug acquisition cost being the primary contributor. However, this can be offset by an improvement in clinical management and PBMEAs.