Background Macitentan is a new endothelin receptor antagonist (ERA) which was compared with placebo in the SERAPHIN trial. The results showed no superior efficacy or safety compared (indirectly) with other ERAs but better hepatic tolerance.

Purpose To assess adaptation of pulmonary arterial hypertension (PAH) treatment prescriptions under our hospital protocol and its economic impact, and to describe the clinical results of using a new ERA, macitentan.

Material and methods A use protocol for ERAs was established in September 2016 in our hospital, evaluating cost effectiveness as the main criterion for prescription. Thus bosentan was chosen as the first option for treatment as macitentan had not shown superiority with regard to either efficacy or safety. According to the use protocol, macitentan should be used in naïve patients with liver dysfunction or in those patients treated with bosentan who have developed treatment related hepatic toxicity. Several clinical parameters assessed PAH disease before and after treatment: functional class, baseline oxygen saturation (%SpO₂) and NT-proBNP levels.

Results After designing the use protocol for ERAs, 9 prescriptions for macitentan from the respiratory department were registered. 44% of patients (4/9) met the requirements of use of macitentan (increased transaminases before using bosentan). The treatment cost per month with a standard maintenance dose of bosentan 125 mg/12 hours was €414, while the treatment cost per month with a standard dose of macitentan 10 mg/24 hours was €2063. After 4 months of treatment with macitentan, patients with elevated transaminases had returned to normal levels but all patients maintained the same functional class and there were no clinically significant differences in%SpO₂ or NT-proBNP (p>0.05).

Conclusion If compliance with the use protocol for ERAs had been 100%, 5 of the patients would have been treated with bosentan, leading to a cost saving of about €1649 for patient per month, a total amount of €74205 so far this year. Implementation of a consensual use protocol for ERAs could enhance the rational use of this drug, but further collaboration with physicians is needed to achieve better optimisation of available resources.

No conflict of interest