Macitentan and tadalafil combo beneficial for pulmonary arterial hypertension patients

USA: The use of macitentan and tadalafil combination therapy proved beneficial in patients with newly diagnosed pulmonary arterial hypertension (PAH), according to a recent study presented at the CHEST Annual Meeting 2019 in New Orleans.

Treatment with the combination drug resulted in hemodynamic progress, as well as improvements in function and risk profile in PAH patients.

According to the American Lung Association, pulmonary arterial hypertension is one form of a broader condition known as pulmonary hypertension, which means high blood pressure in the lungs. In PAH, increased pressure in the vessels is caused by obstruction in the small arteries in the lung, for a variety of reasons. Current guidelines recommend early treatment with an endothelin-receptor antagonist (ERA) and a phosphodiesterase type-5 inhibitor (PDE-5).

Olivier Sitbon, MD, PhD, from Université Paris–Sud, who will present the study findings at the CHEST Annual Meeting 2019 in New Orleans, and colleagues evaluated 46 newly diagnosed, treatment-naive adult PAH patients with medium functional ability who enrolled in the OPTIMA trial, a prospective, multicenter, single-arm, open-label, phase IV trial designed to evaluate the efficacy, safety and tolerability of initial oral combination therapy using macitentan and tadalafil. Using data from week 16, the investigators found that:

• Macitentan and tadalafil combination therapy eased blood circulation in the lungs by 47%.


• The mean six-minute walk distance increased by 35.8 meters.


• Approximately 63% of patients had an improvement in their functional ability.


• The patients tolerated the treatment well.

"Our findings add new evidence to the benefit of initial oral double combination therapy in patients with pulmonary hypertension," concluded Dr. Sitbon.

Macitentan, an endothelin receptor antagonist, reduces the production of endothelin, decreasing lung blood vessel constriction and lowering blood pressure in the pulmonary arteries. Phosphodiesterase type-5 inhibitors, such as tadalafil, are used as a targeted therapy to slow pulmonary hypertension progression and, in some cases, reverse some heart and lung damage.