Abstract
Transition from parenteral prostanoids to oral selexipag may be considered in select patients with pulmonary arterial hypertension (PAH) to reduce the therapeutic burden imposed on patients and caregivers, but its safety and efficacy remain uncertain. A retrospective cohort study was conducted involving adult patients with PAH who transitioned from parenteral prostanoids to selexipag at Canadian tertiary referral centers between January 2016 and November 2020. The primary outcome was transition failure at 12 months, defined as a composite of death or PAH-related worsening. Baseline predictors of transition failure were identified using univariate Cox regression, with follow-up data collected up to 36 months post-transition or until site-specific data submission, occurring between May 2021 and February 2023. At 12 months post-transition, 11 of 36 patients (31%) experienced transition failure, including 4 deaths, all classified as high-risk pre-transition. Of the 25 patients (69%) who successfully transitioned, only one (4%) experienced transition failure over the subsequent observation period (median follow-up 28 months). Pre-transition variables protective against transition failure included a right atrial pressure (RAP) < 8 mmHg (HR 0.290, 95% CI 0.084-0.999, p = 0.049), absence of hospitalizations in the year preceding transition (HR 0.239, 95% CI 0.064-0.885, p = 0.032), lower brain natriuretic peptide (< 50 pg/mL)/N-terminal pro-B-type natriuretic peptide (< 300 pg/mL) levels (HR 0.174, 95% CI 0.045-0.676, p = 0.011), and REVEAL 2.0 score < 7 (HR 0.162, 95% CI 0.049-0.541, p = 0.003). These findings suggest that transition from parenteral prostanoids to selexipag carries the risk of clinical deterioration and should only be considered in carefully selected, low-risk patients.