The Food and Drug Administration (FDA) recently approved Tracleer, a new oral medication for the treatment of pulmonary arterial hypertension (PAH), a rare but fatal type of high blood pressure. PAH causes abnormally high blood pressure in the arteries connecting the heart and lungs.
Tracleer, made by Actelion Pharmaceuticals of San Francisco, blocks the action of endothelin, a hormone that narrows blood vessels and elevates blood pressure. High concentrations of endothelin are often found in patients suffering from PAH. The popular diet drugs Fen-Phen, Pondimin, and Redux can cause pulmonary hypertension.
The FDA's Cardiovascular and Renal Drugs Advisory Committee conducted a study involving 245 PAH patients who were given Tracleer for three months. Researchers found that Tracleer recipients were able to walk 35 feet farther with the aid of the drug. The FDA called these results "extremely impressive."
Tracleer, known chemically as bosentan, is not without complications. The FDA warns that the drug may cause liver toxicity and birth defects.