RATIONALE: Patients diagnosed with pulmonary arterial hypertension (PAH) and connective tissue disorders (CTD) have a poorer prognosis than those diagnosed with PAH not associated with CTD. In the pivotal GRIPHON study, the efficacy and safety of selexipag in patients with CTD-associated PAH was consistent with that observed in the overall population. This study aimed to assess the impact selexipag in CTD-associated PAH (PAH-CTD) and PAH not associated with CTD (PAH non-CTD) in real world clinical practice.
METHODS: Using Optum De-identified Clinformatics database, PAH-CTD and PAH non-CTD patients, aged ≥18 years and treated with selexipag were identified between 01DEC2015 to 31DEC2019 from the US population. The index date was defined as the date of the first selexipag claim and was required to have occurred on or after the first observed PAH diagnosis to select patients newly prescribed to selexipag. Patients were required to have ≥12 months of continuous enrollment before index date and were followed until earliest of selexipag discontinuation, health plan disenrollment, death, presence of a diagnosis claim for chronic thromboembolic pulmonary hypertension, or study end. Multivariable regression analyses adjusting for baseline demographic and clinical characteristics were used to compare time to hospitalization, disease progression, and PAH- and all cause related medical (inpatient and outpatient) costs between the two cohorts with PAH non-CTD as reference. Disease progression was defined as time to earliest of IV/SC prostanoid initiation, PAH-related hospitalization, PAH-related ER visit, lung transplant, balloon atrial septostomy, or all-cause death.
RESULTS: A total of 80 PAH-CTD and 237 PAH non-CTD patients newly prescribed selexipag were included in the analysis. PAH-CTD patients when compared to PAH non-CTD were younger, proportionately more females, and had lower Charlson Comorbidity Index. There was no significant difference observed in risk of PAH-related hospitalization (hazard ratio [HR]=1.13; p=0.641), all-cause hospitalization (HR=1.09; 95% p=0.764), and disease progression (HR=1.14; p-value=0.522). PAH-related medical costs were similar between the cohorts (($2,568 vs $2,059, p=0.156). PAH-CTD patients incurred higher mean all-cause medical costs compared to PAH non-CTD ($6,312 per patient per month [PPPM] vs $4,663, p=0.047).
CONCLUSION: The study suggests that risk of all-cause and PAH-related hospitalization, and disease progression was not different among PAH-CTD and PAH non-CTD selexipag-treated patients. Treatment with selexipag in the real-world appears to confer similar clinical benefits in both patient groups. PAH-related medical costs were not different between the two cohorts whereas all-cause costs were significantly higher in PAH-CTD patients suggesting the incremental burden associated with CTD.