The Janssen Pharmaceutical Companies of Johnson & Johnson announced the submission of a New Drug Application (NDA) to the US Food and Drug Administration (FDA) seeking approval of an investigational single tablet combination therapy of macitentan 10mg and tadalafil 40mg (M/T STCT) for the long-term treatment of pulmonary arterial hypertension (PAH, World Health Organization [WHO] Group 1) in adult patients with WHO functional class (FC) II-III. The application is based on positive data from the phase 3 A DUE study, which met its primary endpoint and demonstrated that M/T STCT significantly improved pulmonary haemodynamics (blood flow through pulmonary blood vessels) versus macitentan and tadalafil monotherapies in this PAH patient population.