MediciNova Inc. said the U.S. Food and Drug Administration granted orphan-drug designation to MN-166, or ibudilast, as an add-on therapy to temozolomide for treating brain cancer.

Temozolomide, marketed as Temodar by Merck & Co. Inc., is a chemotherapy drug used to treat glioblastoma, an aggressive and extremely lethal form of brain cancer.

The U.S. FDA's orphan-drug designation is designed to encourage the development of rare disease therapies through incentives including seven years of marketing exclusivity.

La Jolla, Calif.-based MediciNova is a biopharmaceutical company involved in developing therapies for serious diseases with unmet medical needs. It has been marketing ibudilast in Japan and South Korea since 1989 to treat post-stroke complications and bronchial asthma. The company is developing the drug, an anti-inflammatory and neuroprotective oral agent, for progressive multiple sclerosis and other neurological conditions such as ALS and substance abuse/addiction.