Objective: To describe the clinical efficacy in our population of Macitentan in PH patients.
MATERIAL AND METHODS: A prospective, consecutive, open, phase IV registry of patients with PH who started treatment with M (Opsumit MR) in Argentina, from March 2015 to November 16, was performed. We included those p who received M for at least 6 months or presented an event. Baseline characteristics, functional class (FC), 6-minute gait test (TM6M), adverse effects and survival were determined according to the recommendations of the national and international guidelines, at baseline and at 6 month. Clinical efficacy was determined by the improvement in FC from III-IV (advanced) to FC I-II (not advanced), and improvement in 6MWT> 15%. The data was loaded into an Excel database and evaluated with the Bioestat 5.0 program. The normality of the sample was analyzed by the D'Agostino-Pearson test. In relation to the distribution, the t test was used for quantitative variables, Chi² for qualitative and McNemar test for paired variables. A p value of <0.05 was defined as a significant difference between baseline and 6 months.
Results: We included 151 p, 74% women, the average of age was 46 years (28-63) and 98.4% had HP group 1. 98.6% received M 10 mg and 1.4% 5 mg. At baseline, functional class evaluation presented the following distribution: FC I 2.4%, II 19.4%, III 65.3% and IV 12.9% (advanced FC 78.2%). The mean baseline TM6M was 321 m (250-400). At 6 months FC I was 13.5%, II 62.2% and III 24.3% (advanced FC 24.3%), with significant statistical benefit (p <0.001). The mean TC6M reached 397.2 m (320-467), an increase of 24%, with a significant difference (p <0.0001, 95% IC-533-51.6).
Conclusion: In our PH registry, administration of Macitentan was associated with a significant benefit in achieving the objectives of functional class improvement and the distance reached in the 6MWT (76 meters), at 6 months. These data are in agreement with those obtained in the randomized study SERAPHIN.