FDA OKs First Rare Lung Disease Drug

FDA approval of Pfizer subsidiary Wyeth’s Rapamune for lymphangioleiomyomatosis may be the light at the end of the tunnel for sufferers of the extremely rare lung disease.

LAM, which primarily affects women of childbearing age, causes gradual loss of lung function as smooth muscle cells invade the airways, shutting the lungs down. And until now, there were no available treatments that could help patients avoid or delay lung transplantation.

Wyeth studied the drug in 89 patients for a total of two years and found that patients given Rapamune (sirolimus) lost significantly less lung capacity than patients on placebo — approximately 11 percent of expected adult lung capacity.

Those results landed the drug breakthrough therapy designation, orphan drug designation and priority review, which gave Wyeth a shortened six-month review period plus seven years of marketing exclusivity.

The FDA estimates that only two to five women per million have the disease worldwide.

Rapamune was originally approved in 1999 as an antirejection drug for patients ages 13 and older who have undergone a kidney transplant. —Lena Freund