Why is Pfizer testing one of its existing products as a treatment for children with a rare lung disorder? At the FDA's request, the pharma giant is looking at a form Viagra--sold as the blood-pressure treatment called Revatio in adults--in this patient population. And if regulators can agree on how to test it, the drug could get an additional six months of patent life.
Doctors are already using Revatio to treat pulmonary arterial hypertension in kids, and some say it doesn't carry as many side effects as alternative treatments. The disorder affects some 600 children a year.
Pfizer is meeting with an FDA advisory panel tomorrow to hash over the results of a study of 234 kids. At issue is the measurement method used to determine whether Revatio was working: In adults, it's an exercise test, but Pfizer says that test was hard to do with young kids. The company wants FDA to consider data from a catheter-based test. Using the latter measure, Revatio showed a significant benefit, Bloomberg reports.
Here's what's at stake: Viagra accounted for $1.89 billion of Pfizer's sales last year, with another $450 million on top of that from the Revatio brand. Six months' additional revenue would thus be a billion-dollar-plus proposition. The '534 patent covering Viagra expires in 2012.
- read the Bloomberg story