Corcept skyrockets on FDA nod for rare disease drug

U.S. regulators have green-lighted Corcept Therapeutics' drug Korlym (mifepristone), the first FDA-approved treatment for Cushing's syndrome. It's also the company's maiden marketed product.

Menlo Park, CA-based Corcept's shares jumped more than 40% in after-hours trading on news of the approval.

The newly approved drug blocks the activity of the steroid cortisol, which is overproduced in the adrenal glands of Cushing's patients and causes blood pressure to rise. The treatment works by preventing the hormone from binding to its receptor, according to the FDA.

Korlym is the latest example of the rare disease drug development model in action, showing that companies can gain approvals for treatments against conditions affecting small pools of patients--and do so with evidence from relatively tiny clinical trials. The drug, which was granted orphan status in 2007, is expected to benefit about 5,000 patients in the U.S. Its approval was based largely on a clinical trial involving just 50 patients.

However, Corcept's drug comes with an advisement against its use in pregnant women, as it uses an ingredient from an abortion drug. The company believes the inclusion of that ingredient could limit its use, Bloomberg reported.

Biopharma outfits both large and small are banking on the rare-disease field, which helps patients with unmet medical needs and offers such advantages as extended exclusivity periods and lower costs of clinical development.

- here's the FDA release
- check out Bloomberg's story