Encysive Pharmaceuticals, a biopharmaceutical company engaged in the discovery, development and commercialization of novel, synthetic, small molecule compounds, announced plans to market Thelin (sitaxsentan sodium) directly in Europe.
Thelin, an oral, once daily, highly selective endothelin receptor antagonist, is currently being evaluated by the US Food and Drug Administration (FDA) as a new treatment for pulmonary arterial hypertension (PAH), a company release said.
“Following the positive results of our second pivotal phase III study, Stride-2, and after comprehensive evaluation by management, the board of directors has concluded that the company will market directly in Europe,” commented John M. Pietruski, chairman of the board of Encysive Pharmaceuticals.
“The PAH market in Europe has undergone rapid expansion, but remains a highly efficient, specialist-driven market to which Encysive is well positioned to effectively market Thelin,” added Bruce D. Given, president and CEO of Encysive Pharmaceuticals.
Encysive submitted a New Drug Application with the FDA for Thelin in May. The company anticipates filing for European approval in the third quarter of 2005.
Thelin is a small molecule that blocks the action of endothelin, a potent mediator of blood vessel constriction and growth of smooth muscle in vascular walls. Endothelin receptor antagonists may prove to be effective in the treatment of a variety of diseases where the regulation of vascular constriction is important. Thelin is 6,500-fold selective in the targeting of the endothelin A receptor versus the endothelin B receptor.
Pulmonary arterial hypertension (PAH) is a condition that involves high blood pressure and structural changes in the walls of the pulmonary arteries, which are the blood vessels that connect the right side of the heart to the lungs. PAH causes shortness of breath, limits activity, and is eventually fatal unless treated successfully with heart/lung or lung transplantation. PAH is estimated to afflict approximately 100,000 to 200,000 people worldwide, many of whom are children and young women.
The most frequent adverse events that occurred in patients receiving Thelin, which were more common than in placebo-treated patients, were headache, edema, nausea, upper respiratory tract infection, dizziness, insomnia, nasopharyngitis, and nasal congestion. Because Thelin inhibits the metabolism of warfarin, a decreased dose of warfarin is needed when co-administered with Thelin.