Also Known As: Bosentan, Tracleer
Bosentan is a dual endothelin receptor antagonist used in the treatment of pulmonary artery hypertension (PAH). It is licensed in the United States, the European Union and other countries by Actelion Pharmaceuticals for the management of PAH under the trade name Tracleer.
Bosentan is a competitive antagonist of endothelin-1 at the endothelin-A (ET-A) and endothelin-B (ET-B) receptors. Under normal conditions, endothelin-1 binding of ET-A or ET-B receptors causes constriction of the pulmonary blood vessels. By blocking this interaction, bosentan decreases pulmonary vascular resistance. Bosentan has a slightly higher affinity for ET-A than ET-B.
Bosentan is indicated mainly for the treatment of pulmonary hypertension. In 2007, Bosentan was also approved in the European Union for reducing the number of new digital ulcers in patients with systemic sclerosis and ongoing digital ulcer disease.
In the United States, Bosentan is indicated for the treatment of pulmonary arterial hypertension (WHO Group I) in patients with WHO Class II-IV symptoms, to improve exercise capacity and decrease the rate of clinical worsening.
Hormone-based contraception is not possible in women taking Bosentan, due to a pharmacokinetic interaction. Therefore, other highly reliable forms of contraception should be used instead.
Bosentan is contraindicated in pregnancy because of its teratogenicity (Pregnancy Category X).