(Reuters) – The U.S. Food and Drug Administration on Thursday approved a first of its kind drug from Shire Plc to treat patients aged 12 and older suffering from a rare hereditary disease that causes swelling.

The drug, Takhzyro, is expected to bring in blockbuster sales for Shire, and is important to Japan’s Takeda Pharmaceutical Co Ltd, which plans to buy the Dublin-based rare disease specialist for $62 billion.

The monoclonal antibody, previously known by its chemical name lanadelumab, was approved https://www.fda.gov/Drugs/DrugSafety/ucm618261.htm?utm_campaign=FDA%20approves%20new%20treatment%20for%20hereditary%20angioedema%20%28HAE%29&utm_medium=email&utm_source=Eloqua to treat patients with types I and II hereditary angioedema (HAE), a disease that affects about 1 in 50,000.

There are only a handful of treatments available for HAE, including some from Shire. The disease affects people who have low levels of a certain protein and results in episodes of severe swelling in different areas such as the stomach, limbs, face and throat.

(Reporting by Tamara Mathias in Bengaluru; Editing by Maju Samuel)