Macitentan in Children with Pulmonary Arterial Hypertension: A Multicenter Experience

Abstract

Macitentan seems to improve outcomes in patients with pulmonary arterial hypertension (PAH). Nevertheless, safety and efficacy in pediatric patients is still to be determined. Multi-center, observational study to assess safety and efficacy of oral macitentan in patients under 18 years-of-age from the Spanish Registry of Pediatric Pulmonary Hypertension with group 1 PAH. Outcome measures included changes in the World Health Organization Functional Class (WHO FC) from baseline to month 6, 6-min walking distance (6MWD), NT-proBNP levels, risk-stratification, echocardiographic and hemodynamic parameters, and Pediatric Quality of Life Inventory. Seventy-four patients (median age 9.6 years) with PAH were included in the study, of which thirty-one had idiopathic/heritable pulmonary arterial hypertension and 43 had PAH associated with congenital heart disease. Significant clinical improvement was observed after 6 months of treatment with macitentan: The percentage of patients on WHO FC III/IV decreased from 48 to 22% (p = 0.001); mean 6MWD (n = 42) increased significantly in around 45 m (p = 0.032); NT-proBNP decreased a mean of - 438.9 ± 175 pg/ml, (p = 0.015). There was a 17% increase in the number of patients meeting all three low-risk parameters of 17% (p = 0.002). Side effects were detected in four patients (5.4%). Macitentan was discontinued in one patient. Disease progression was observed in 6 patients despite macitentan therapy. This study provided evidence on the clinical benefits and good tolerance of macitentan in paediatric population with group I PAH treated in routine clinical practice.

Keywords: Children; Efficacy; Macitentan; Pulmonary hypertension; Safety.