Viagra's alternate use gives Pfizer extra 6 months before patent expires

Pfizer Inc,'s erectile dysfunction drug Viagra finds an alternative use, could be used to treat a rare lung disorder among children.

The lung disorder is called pulmonary arterial hypertension a condition that increases the blood pressure in the artery or capillaries resulting in fainting, dizziness and shortness of breath. It causes the right side of the heart to work harder.

Viagra blocks an enzyme that regulates the flow of blood in the penis and lungs. It helps adults with pulmonary arterial hypertension by easing the arterial wall leading to less pressure and resistance. The FDA is trying to figure the best approach to measure the effectiveness of the drug among children.

Pfizer tested some 234 children with the drug. However it had to change the method to ascertain the effectiveness of the drug on children. It used exercise to measure the effectiveness on adults but in children it had to use a catheter to measure the flood flow. The drug failed to show results when children were put through the exercise regimen, but the catheter test revealed positive results.