Structural Enablers of Rare Disease Treatment Coverage in Latin America and the Caribbean: Lessons from Emicizumab.

We examine how structural characteristics of health systems in Latin America and the Caribbean (LAC) shape access to innovative therapies, using emicizumab for hemophilia A as a case study. Although the therapy is available in the region, access remains uneven and constrained by high costs and fragmented health system arrangements. Using a descriptive structural approach, we characterize the health system configurations associated with financial coverage of emicizumab across 16 LAC countries, representing more than 85% of the regional population. Regulatory approval timelines and coverage status were described, and principal component analysis (PCA) was applied to synthesize multiple indicators into a Global Characteristics Index capturing five core health system functions: resource generation, financing, service delivery, general governance, and therapy-specific governance. Coverage is defined as formal access with explicit financial protection provided by the health system. Substantial heterogeneity was observed across countries. Regulatory approval was often achieved relatively rapidly, but this did not consistently translate into timely or comprehensive coverage. Countries with stronger structural characteristics-particularly in resource generation, service delivery, and governance-tended to achieve broader and more sustained coverage, although institutional capacity alone was not sufficient in all cases. Our results emphasize the need to strengthen health governance and adopt specific policies for rare diseases in the region.