Transforming PAH care in Italy: a clinical and economic evaluation of sotatercept add-on therapy.

Background and aim: Pulmonary arterial hypertension (PAH) is a rare, progressive disease associated with significant morbidity and mortality. Recent clinical studies (STELLAR [NCT04576988] and ZENITH [NCT04896008]) showed that adding sotatercept to standard of care improves clinical outcomes in patients with PAH. This study aimed to assess the clinical and economic impact of gradually adding sotatercept to currently available treatments for PAH in Italy. Methods: A Markov model was developed to simulate the disease pathway of PAH patients. The model consisted of six health states: low risk PAH, intermediate-low risk PAH, intermediate-high risk PAH, high risk PAH, post lung/heart transplant, and death. Using this model, a cost-consequence analysis was performed to calculate the number of PAH related health events and associated costs over a 3-year time horizon assuming a gradual increase in the use of sotatercept. Primary outcomes included number of hospitalizations, lung/heart transplants, PAH-related deaths, and disease management costs. Sensitivity analyses were conducted to examine model robustness. Results: Over a 3-year time horizon, the model predicted a total of 270 deaths, 1 lung/heart transplantation and 430 hospitalizations in the scenario with sotatercept. For the scenario without sotatercept, the model projected a total of 408 deaths, 2 transplants and 720 hospitalizations. Adding sotatercept to background therapy resulted in a reduction of 289 hospitalizations, 1 transplant and 138 deaths. Associated disease management costs were estimated to be €33.8 million in the scenario with sotatercept and €38.2 million in the scenario without sotatercept. Sotatercept plus background therapy was also associated with a reduction in costs of €4.4 million (11.8%). Discussion and conclusions: This cost-consequence analysis showed that the introduction of sotatercept as an add-on therapy for the treatment of patients with PAH in Italy has the potential to reduce mortality, hospitalizations and lung/heart transplants, thereby substantially reducing PAH disease management costs.