Drugs Xagena
European Medicines Agency ( EMEA ) has approved Revatio ( Sildenafil citrate ) for the treatment of pulmonary arterial hypertension ( PAH ), a rare, aggressive and life-shortening vascular disease.
Revatio is classified by the EMEA as an orphan drug.
Medicines granted orphan drug status are intended for rare and serious or life-threatening diseases that affect fewer than five in 10,000 persons, or are medicines unlikely to be developed under normal market conditions.
Revatio was approved for the treatment of patients with pulmonary arterial hypertension classified as WHO functional class III, to improve exercise capacity. Efficacy has been shown in primary pulmonary hypertension and pulmonary hypertension associated with connective tissue disease.
The EMEA approval was based on the results of a double-blind, placebo-controlled study of 278 patients with pulmonary arterial hypertension.
Patients were randomized to three different dosages of Revatio ( 20 mg, 40 mg, or 80 mg ) three times a day or placebo.
All three treatment groups showed statistically significant improvements in the primary endpoint of six-minute walk distance. No significant differences were observed between the three dosages in six-minute walk distance, thus the approved dose is limited to 20 mg three times daily.
Patients taking Revatio also showed statistically significant improvements in other important measures of cardiac function.
Patients were followed for an additional year as part of an open-label extension trial. Improvements in walk distance and cardiac function were preserved, with Revatio patients showing a 96 percent survival rate, compared to an expected survival rate of 71 percent.
Revatio was generally well tolerated at all doses. The most common side effects were similar to the established safety profile of Viagra used for the treatment of erectile dysfunction, including headache, dyspepsia, flushing, epistaxis, and insomnia.
The use of Revatio or Viagra and organic nitrates in any form, at any time, is contraindicated.
Source: Pfizer, 2005
XagenaMedicine_2005
