Bosentan for patients with steroid-resistant pulmonary sarcoidosis: a randomised controlled trial

Sarcoidosis is a disorder of unknown aetiology. Most patients have steroid-responsive disease, but side effects and steroid resistance may necessitate alternative treatments. Endothelin has in-vitro fibrogenic activity and the endothelin system is activated in sarcoidosis.

We studied the efficacy and safety of the endothelin receptor antagonist bosentan in sarcoidosis patients.

In a prospective 12-month, double-blind, 1:1-randomised, placebo-controlled phase II trial, we assessed the effect of bosentan in patients with steroid-resistant sarcoidosis and with impaired exercise capacity and/or resting lung function. Primary endpoints were safety and overall response rate of total lung capacity, diffusion capacity, peak oxygen uptake, 6-minute walking distance and chest computed tomography score. Secondary endpoints included adverse events and quality of life.

Twenty patients were randomised. Three patients discontinued the study medication prematurely. No serious drug-related adverse events occurred. At 12 months no statistically significant differences were observed in the primary endpoints including total lung capacity, diffusion capacity, 6-minute walking distance, peak oxygen uptake, and computed tomography-score. Sixty-three percent of the patients treated with bosentan showed an increase of 10% in at least one of the primary endpoints, compared with 67% in the placebo group (p = 1).

There is no evidence to support efficacy of bosentan as an antifibrotic treatment for patients with steroid-resistant pulmonary sarcoidosis. Bosentan was well tolerated and no drug-related adverse effects were observed within the study population.

ISRCTN registry, ISRCTN73579020.