Tracleer shows promise in class II PAH patients

Swiss pharmaceutical group Actelion says that initial data from a trial of its endothelin antagonist Tracleer (bosentan) indicate it has efficacy as a therapy for mildly symptomatic pulmonary arterial hypertension patients. Specifically, the data show that treatment confers a significant reduction in pulmonary vascular resistance and a delay in the worsening of clinical symptoms, in addition to demonstrating a strong trend towards improved excercise capacity.

The findings are based on the analysis of six-month treatment data from the Phase IIIb EARLY (Endothelin Antagonist tRial in miLdly sYmptomatic PAH patients, NYHA modified functional class II) study. Enrollees in the double-blind, placebo-controlled program were provided with a 62.5mg per day dose of the drug for an initial four-week period, followed by five months of treatment at 125mg daily. Actelion added that it will undertake a review of the data to support planned regulatory filings that will seek to expand the drug's list of approved indications. The agent was first cleared in the USA for the treatment of PAH sufferers with NYHA (New York Heart Association) modified functional class III and IV disease.

Analysts at Lehman Brothers said they anticipate that the Tracleer label extension will be approved by regulators worldwide, but added that they would not be revising their sales forecasts because the drug is already used "off-label" for the treatment of this patient group.