Patient and caregiver spinal muscular atrophy treatment attribute preferences in Latin America

Spinal muscular atrophy (SMA) is a rare, progressive neuromuscular disease associated with a significant burden of illness to both patients and caregivers; however, there is little evidence available regarding how patients and caregivers evaluate potential treatment benefit-risk profiles. As access to SMA disease-modifying therapies increases, it is imperative to understand which treatment attributes drive treatment choices.

To identify which treatment attributes drive treatment choices in adults with SMA and caregivers of children with SMA across nine countries in Latin America.

A discrete choice experiment (DCE) survey was developed for market research using data collected via qualitative interviews and consultations with medical experts. Adults with Type 2/3 SMA and caregivers of children with Types 1-3 SMA were recruited by patient advisory groups and physician referrals. Respondents completed a 30-min, online survey that collected patient demographics, disease-specific information, and quality of life data (via the EQ-5D-5L), and included the DCE, in which respondents were asked to choose between 14 sets of hypothetical treatment profiles. Data were pooled for analysis, as the country-level sample sizes were small. Raw data were aggregated in Microsoft Excel. Statistical testing was performed using data tables and SPSS (as appropriate). Demographic data were summarized descriptively.

A total of 143 respondents (45 adults with SMA and 98 caregivers) completed the online survey. Most respondents were from Argentina (35.0%) or Brazil (19.6%). Breathing function outcome was the most important treatment attribute for caregivers, while adults with SMA placed greater importance on motor function outcome. Both adults with SMA and caregivers placed the greatest importance on improvements in function compared with worse or stable outcomes.

Understanding treatment attribute preferences at a regional level will improve shared medical decision-making for individuals with SMA.