Dublin's Shire PLC said the U.S. Food and Drug Administration granted a priority review of its medicine lanadelumab to treat patients with hereditary angioedema, a rare genetic disease.

Hereditary angioedema, which causes swelling in various parts of a patient's body, affects about one in every 10,000 to 50,000 people in the U.S., according to the U.S. Hereditary Angioedema Association.

The FDA accepted Shire's biologic license application for lanadelumab and expects to make a decision by Aug. 26.

The application is based on data from four clinical trials.

The regulator grants priority review to drugs with the potential to provide significant improvements for treating, diagnosing or preventing a serious disease. The designation accelerates the review target of a drug to eight months, compared to the standard 12 months.

Lanadelumab is touted as a so-called blockbuster drug — a medicine with the potential to generate more than $1 billion in revenues —having met its main goal in a late-stage trial. The drug showed an 87% fall in attacks compared with placebo and was well-tolerated in patients in the 26-week study.

Meanwhile, rival BioCryst Pharmaceuticals Inc. in May 2017 also reported positive phase 2 trial results for its own hereditary angioedema drug, BCX7353.