Four-Strata Risk Assessment in Patients with Pulmonary Arterial Hypertension Treated with Selexipag in Real-World Settings (EXPOSURE Study).

introductionRisk assessment can aid management of pulmonary arterial hypertension (PAH) and clinical decision-making. This analysis describes characteristics, treatment patterns and outcomes of patients with PAH, categorised by risk status at time of treatment escalation with selexipag in clinical settings.

methodsPatients initiating selexipag in the ongoing multicentre, prospective EXPOSURE (EUPAS19085) study were grouped as low, intermediate-low, intermediate-high or high risk of 1-year mortality according to the ESC/ERS 4-strata method.

resultsAs of November 2022, 77% (535/698) of patients initiating selexipag had data allowing for risk calculation; 14% (N = 76) were low, 31% (N = 168) intermediate-low, 34% (N = 182) intermediate-high and 20% (N = 109) high risk of 1-year mortality. Overall, patients were predominantly female (71%), with idiopathic/heritable PAH (56%) or PAH associated with connective tissue disease (CTD-PAH; 27%), median age of 60 years and prevalent (2 years) disease. From low to high risk, proportion of CTD-PAH and age increased (from 12%-40% and 46-68 years, respectively); time from diagnosis decreased and presence of cardiovascular risk factors increased. Most patients across risk groups (74-81%) initiated selexipag as part of triple oral combination therapy. Overall median (Q1, Q3) selexipag exposure duration was 10.1 (3.5, 24.1) months. Proportions of hospitalised patients increased with increasing risk group (16-42% from low to high, respectively); more hospitalisations were PAH-related for the high risk (71%) versus other risk groups (47-54%). Kaplan-Meier survival estimates were 98%, 98%, 93% and 80% at 1-year and 98%, 92%, 81% and 67% at 2-years, from low to high risk, respectively.

conclusionsIn clinical settings, selexipag is initiated across all risk groups, predominantly as triple therapy. Only 45% of patients being at low/intermediate-low risk at selexipag initiation suggests an opportunity for more frequent patient monitoring and earlier treatment escalation, given that 4-strata risk assessment was prognostic for hospitalisations and survival in this contemporary PAH cohort. A graphical abstract is available with this article.