Macitentan Plus Tadalafil Single‐Tablet Combination Therapy in Chinese Patients With Pulmonary Arterial Hypertension: A Subgroup Analysis of the A DUE Study

Macitentan 10 mg and tadalafil 40 mg single-tablet combination therapy (M/T STCT) has been evaluated in the global A DUE study (NCT03904693). Here, we report the results of a subgroup analysis in participants from China. This double-blind, active-controlled, Phase 3 A DUE study randomized patients with symptomatic pulmonary arterial hypertension (PAH) to receive M/T STCT, macitentan, or tadalafil depending on their baseline PAH treatment (treatment-naïve, endothelin receptor antagonist, or phosphodiesterase Type 5 inhibitor monotherapy). The primary end point was change in pulmonary vascular resistance (PVR) expressed as the ratio of geometric means (GMR) of Week 16 to baseline. A total of 187 patients were randomized, including 23 patients in China. PVR reduction was significantly greater with M/T STCT compared with macitentan (50%) and tadalafil (41%) (adjusted GMRs were 0.50; 95% confidence level [CL]: 0.35-0.72; <i>p</i> = 0.0017 and 0.59; 95% CL: 0.43-0.80; <i>p</i> = 0.0040, respectively) in Chinese patients. M/T STCT was well tolerated in Chinese patients; the safety profile was consistent with that of macitentan and tadalafil monotherapies, and that of the overall population. In conclusion, in Chinese patients with PAH, PVR was reduced with M/T STCT versus either monotherapy after 16 weeks of treatment; the safety profile of M/T STCT was in line with the known safety profile of the individual components and appeared consistent with the overall population, although data should be interpreted with caution due to the small sample size. Our findings support the use of M/T STCT for PAH in China. <b>Trial registration</b>: ClinicalTrials.gov https://clinicaltrials.gov/ NCT03904693 (April 5, 2019).