FDA backs Koselugo, first drug for debilitating and disfiguring rare disease

The US Food and Drug Administration on Friday approved Koselugo (selumetinib) for the treatment of pediatric patients, two years of age and older, with neurofibromatosis type 1 (NF1), a genetic disorder of the nervous system causing tumors to grow on nerves.

Koselugo, which has disappointed in several cancer trials, is the first drug approved by the FDA to treat this debilitating, progressive and often disfiguring rare disease that typically begins early in life, and this MEK inhibitor is being by originator Anglo-Swedish drugmaker AstraZeneca (LSE: AZN) and US pharma giant Merck & Co (NYSE: MRK) under their wider global licensing agreement.

Koselugo is approved specifically for patients who have symptomatic, inoperable plexiform neurofibromas (PN), which are tumors involving the nerve sheaths (coating around nerve fibers) and can grow anywhere in the body, including the face, extremities, areas around the spine and deep in the body where they may affect organs. Koselugo is a kinase inhibitor, meaning it functions by blocking a key enzyme, which results in helping to stop the tumor cells from growing.