Results of the MACiTEPH study of macitentan for the treatment of inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension

BACKGROUND: In a phase 2 study of inoperable chronic thromboembolic pulmonary hypertension (CTEPH), macitentan 10 mg improved hemodynamics and exercise capacity. METHODS: MACiTEPH (NCT04271475) was a prospective, double-blind, placebo-controlled, phase 3 study. Adult patients with inoperable CTEPH (with/without balloon pulmonary angioplasty [BPA]) or persistent/recurrent CTEPH after pulmonary endarterectomy (PEA) (with/without BPA) were randomized 1:1 to macitentan 75 mg or placebo once daily. Primary endpoint was change from baseline to Week 28 in 6-minute walk distance (6MWD). RESULTS: Following a pre-planned interim analysis, the study was stopped for futility. 127 patients were randomized, predominantly with inoperable CTEPH with BPA (36.2%) or persistent/recurrent CTEPH after PEA without BPA (30.7%). The majority (81.9%) were receiving pulmonary hypertension (PH)-specific therapy at baseline. 47 patients in the macitentan 75 mg and 48 in the placebo group had Week 28 assessments. Primary endpoint was not met; mean change in 6MWD from baseline to Week 28 versus placebo was -16.1 m (95% confidence limit: -32.3, 0.16). Clinical worsening events occurred in 6.3% and 14.3% of patients in the macitentan 75 mg and placebo groups, respectively. A slightly higher proportion of the macitentan 75 mg group had

• Jenkins, D. P.
• Cerovic, S.
• Csonka, D.
• Ghofrani, H. A.
• Guth, S.
• Heresi, G. A.
• Humbert, M.
• Jaumdally, N.
• Jing, Z. C.
• Lack, G.
• Madani, M. M.
• Matsubara, H.
• Mayer, E.
• McGuire, E.
• Kim, N. H.