Treatment with Tracleer in mildly symptomatic pulmonary arterial hypertension (PAH) patients was associated with a highly significant reduction in pulmonary vascular resistance compared to placebo, a primary endpoint of the study. Patients on Tracleer also showed a strong trend towards improvement in 6-minute-walk test, another primary endpoint. The study met its main secondary endpoint, as treatment with Tracleer was associated with a significant delay in time to clinical worsening, representing a 70% reduction in risk.
The company will now fully analyze the data in anticipation of planned upcoming regulatory filings worldwide to expand the Tracleer indication to include mildly symptomatic PAH patients. Tracleer was first approved in the US in late 2001 for PAH patients.
Actelion said, however, that in clinical trials approximately 11% of PAH patients receiving Tracleer experienced abnormal but reversible liver enzyme elevations and advised that as a result patients should undergo monthly liver monitoring.