• Primary Pulmonary Hypertension
• Pulmonary Hypertension
• Pulmonary Arterial Hypertension
• PPH Symptoms
• PPH Diagnosis
• PPH Causes
• PPH Treatment
  • Ambrisentan
  • Tracleer
  • Flolan
  • Remodulin
  • Prostacyclin
  • Lung Transplants
  • Thelin
• Diet Drugs and PPH
• Legal Remedies for PPH

Thelin Treatment for Pulmonary Arterial Hypertension

Thelin is the brand name for sitaxsentan / sitaxsentan sodium, a drug that has been developed by Encysive Pharmaceuticals Inc. for the treatment of pulmonary arterial hypertension (PAH). Thelin is currently awaiting Food and Drug Administration (FDA) approval.

Pulmonary arterial hypertension is a deadly type of lung disease that is characterized by a higher-than-normal blood pressure in the pulmonary artery (exceeding 25 mmHg). PAH is often referred to as primary pulmonary hypertension (PPH), instances of which can cause the gradual degrading of the heart and lungs, culminating in patient death.

Although Thelin has been manufactured with the aim of serving as a viable drug treatment for people suffering from PAH, it can be beneficial in the treatment of various diseases requiring the regulation of vascular constriction.

Thelin Treatment - Mechanism of Action

Thelin treats pulmonary arterial hypertension by blocking the action of endothelin, a very potent vasoconstrictor capable of causing severe narrowing of the blood vessels. The scarring and cellular growth associated with PAH is what causes the narrowing of the blood vessels in the lungs. The ensuing backpressure causes the right ventricle of the heart to become overworked as it attempts to supply sufficient oxygen to the bloodstream.

Research has found that patients suffering from PAH display increased levels of endothelin, accelerating vasoconstriction and causing a higher-than-normal blood pressure in the pulmonary artery. As a vasodilator, Thelin counteracts endothelin by inhibiting its effects and relaxing the blood vessels, thereby easing the strain on the right ventricle of the heart.

Thelin Side Effects

Thelin is expected to provide optimal results in the treatment of PAH once the small molecule sodium salt has been approved for widespread use by the FDA. However, like all drugs, there are certain side effects that can be expected when undergoing Thelin drug treatments.

Some of the common Thelin side effects can include:

• Headache
• Swelling caused by excess water retention (edema)
• Nasal congestion
• Insomnia
• Dizziness
• Constipation
• Upper respiratory tract infection
• Liver function abnormalities

Thelin Phase III Clinical Trial - Thelin and Tracleer

Representatives of Encysive Pharmaceuticals Inc. are extremely pleased with the performance of the Thelin Phase III Clinical Trial as the drug edges closer towards FDA approval. The phase III clinical trial was a placebo-controlled study that evaluated the efficacy of 50 mg and 100 mg doses of Thelin compared with Tracleer (brand name for bosentan) in the treatment of pulmonary arterial hypertension.

Tracleer is a type of oral vasodilator drug that has already gained FDA approval for the treatment of PAH. Although Thelin did not provide results that were as successful as those produced by Tracleer, it nonetheless yielded successful results.

Thelin and the FDA

Like all drugs, Thelin requires FDA approval before it can be marketed for the treatment of PAH. Encysive Pharmaceuticals have had to wait patiently for the FDA approval of Thelin, something that many analysts believed would have already occurred. Instead, the FDA is requesting additional information and further testing to ensure that the drug is safe and effective.

PAH Drugs - Thelin vs. Ambrisentan

Although the FDA request does little aside from delaying what is expected to be an eventual approval, some experts believe that it has the potential to derail future sales of Thelin. Ambrisentan is another endothelin receptor antagonist that has been developed by Myogen, a pharmaceutical company competing with Encysive Pharmaceuticals. Developed for the treatment of PAH, Ambrisentan was viewed to be about one and a half years behind the development of Thelin; however, the FDA delays in approving Thelin could open the door to Ambrisentan, allowing Myogen to claim the market share that many assumed would be held by Encysive Pharmaceuticals.

Regardless of which drug receives FDA approval first, both are expected to provide beneficial results in the ongoing treatment of pulmonary arterial hypertension.

Last Revision: April 9, 2008

MediaFact is a noteworthy Internet resource about drug side effects connected with Primary Pulmonary Hypertension and Stevens Johnson Syndrome.