Pfizer's Viagra Could Be Used for Children With Rare Lung Disorder
 

Tiffany Kaiser - July 29, 2010 12:10 PM
 

The FDA meets today to discuss the pill's effectiveness

Children with a rare lung disorder, called pulmonary arterial hypertension, may begin taking Pfizer Inc.'s drug Viagra in order to treat blood pressure-related problems associated with the disorder. 

Viagra is a drug normally used for erectile dysfunction and also helps adults with pulmonary arterial hypertension gain the ability to exercise by relaxing the arterial wall, which leads to decreased pulmonary arterial pressure and resistance. It blocks an enzyme that regulates flow in the penis and lungs.

This medication works for pulmonary arterial hypertension because what this disorder does is increase the blood pressure in the pulmonary vein, artery or capillaries leading to fainting, dizziness and shortness of breath. It causes the right side of the heart to work harder, and Viagra releases this pressure.

U.S. regulators are looking for a way to test whether Viagra would be okay for children. Advisors to the Food and Drug Administration will meet July 29 to discuss this matter and see if Pfizer's study on the pill's effectiveness on children is "sufficient."

Pfizer conducted a study that consisted of 234 children who took Viagra. In most studies of adults with the disorder, they are asked to perform exercise tests. However, this was much too difficult for the children, so a different test where a catheter is inserted through the arteries (which measures blood flow) was conducted instead. This alternative test proved that the drug failed to show any differences when the children tried regular exercise tests, but when researchers used the alternative measure of blood flow, Viagra did prove to be beneficial. 

"It's a good option in pediatric patients because it is well-tolerated, in that it doesn't have as many side effects as some of the other options," said Chad Knoderer, a pediatric clinical pharmacist at Riley Hospital for Children in Indianapolis, who has used Viagra for children with the disorder before.

Pulmonary arterial hypertension affects 600 people a year, and if Pfizer meets FDA requirements, the drug will be on the market an extra six months without generic competition. The patent for the drug is expected to expire in 2012.