Encysive rises on Thelin trial success

The trial, named STRIDE-2, met its primary endpoint of improved six minute walk (6MW) distance in patients receiving a 100mg dose of Thelin (sitaxsentan), with a placebo-subtracted improvement of 31.4 meters.

A 50mg dose of Thelin improved 6MW by 24.2 meters, and bosentan (Actelion’s Tracleer), currently the only approved oral agent for treating pulmonary arterial hypertension (PAH), improved 6MW by 29.5 meters. As expected, placebo patients worsened in 6MW over the 18-week period of the trial.

World Health Organization (WHO) functional class also improved significantly at the 100mg dose of Thelin versus placebo. There were five clinical worsening events in the 100mg patient group, seven events in the 50mg group, 15 events in the bosentan group, and 13 for placebo.

The 100mg dose of Thelin also continued to demonstrate an encouraging safety profile. Liver function abnormalities occurred in 3% of patients in the 100mg Thelin group, compared to 5% in the 50mg Thelin group, 11% in the bosentan group and 6% in the placebo group. Premature discontinuations due to safety or efficacy occurred in four patients at the 100mg Thelin dose, eight at the 50mg Thelin dose, nine in the bosentan group and 11 in the placebo group.

“We are extremely pleased with the performance of Thelin in STRIDE-2,” commented Dr Bruce Given, president and CEO of Encysive Pharmaceuticals. “We will present more details from this trial at appropriate medical meetings over the next several months and we are now focused on filing a new drug application (NDA) with the FDA in April 2005 to seek marketing authorization. This NDA submission will be closely followed by marketing applications in Europe and other territories.”