Costs High for Both SMA Standard Care and Newer Treatments for Post-Symptomatic Patients

The cost burden of standard of care for patients with spinal muscular atrophy (SMA) is substantial, and at current prices approved disease-modifying drugs for the condition have high cost-effectiveness ratios when delivered after symptom onset. Researchers published findings from their systematic review online in the Orphanet Journal of Rare Diseases. 

“[H]uge costs for the later-onset forms [of SMA] are exclusive of new disease-modifying drugs,” researchers wrote. “Nusinersen, the first US Food and Drug Administration (FDA)-approved medication, cost from $516,896 to $907,665 in the first year, and from $258,448 to $457,889 in the second year. (Different prices estimated between 2017 and 2020, in the United States and Europe). Onasemnogene abeparvovec, the second FDA-approved drug, is considered to be the most expensive drug of the world and is priced at $2.1 million in the United States for a single injection.” 

The systematic review included nine studies of the annual cost of care of patients with SMA and six studies of the cost-effectiveness of treatments. 

The most common and severe form of the condition, in which symptoms emerge before a baby is 6 months old, SMA type 1 had an average annual cost of $75,047 to $196,429, according to the study. Later-onset forms—SMA types 2, 3 and 4—had annual costs that ranged from $27,157 to $82,474. The annual totals did not factor in drug costs. 

When researchers considered drug costs, they found that compared with standard of care, nusinersen had an incremental cost-effectiveness ratio (ICER) that ranged from $210,095 to $1.1 million per quality-adjusted life years (QALY) gained. Onasemnogene abeparvovec had an ICER that ranged from $32,464 to $251,403 per QALY.  

For pre-symptomatic patients, ICERs ranged from $206,409 to $735,519, according to the study. For patients with SMA types 2, 3, and 4, ICERs ranged from $275,943 to $8.4 million.  

“Due to the extremely high drug costs, the ICER values for the currently approved SMA therapies are high, and, therefore, treatments are not cost effective,” researchers wrote.  

Nevertheless, they continued, because payers are negotiating for discounts on SMA drugs, study findings may not reflect real-life cost-effectiveness ratios. 

Reference:

Dangouloff T, Botty C, Beaudart C, Servais L, Hiligsmann M. Systematic literature review of the economic burden of spinal muscular atrophy and economic evaluations of treatments. Orphanet J Rare Dis. 2021;16(1):47. Published 2021 Jan 23. doi:10.1186/s13023-021-01695-7