Chiron Wins ‘Orphan’ Status for Drug

Chiron Corp., one of the world’s largest biotechnology companies, said the U.S. government granted its Proleukin drug “orphan drug” status for two types of cancer, a designation that limits competition and gives the company special tax benefits. Chiron said the Food and Drug Administration agreed to the special treatment for use of the drug, also known as IL-2, in treating two relatively rare forms of cancer for which the drug has yet to win FDA approval. IL-2 was originally developed by Chiron competitor Immunex Corp., which now receives royalties from Chiron. It is now approved in the U.S. for treating two forms of cancer that also have the orphan designation--metastatic renal cell carcinoma and malignant metastatic melanoma. The FDA uses the orphan designation to encourage companies to develop drugs for diseases that might otherwise be overlooked. Shares in Emeryville, Calif.-based Chiron rose 25 cents to close at $26.38 on Nasdaq.