FDA Committee Votes in Favor of Dyax Lead Drug for Rare Blood Disease

Xconomy Boston — 

An FDA advisory committee recommended approval of Cambridge, MA-based Dyax‘s (NASDAQ:DYAX) lead drug candidate, ecallantide, to treat severe attacks of a rare blood disease known as hereditary angioedema (HAE), according to an FDA spokeswoman.

The advisory committee members voted 6-5, with two abstentions, that there was enough data to support the approval of the Dyax drug (As with all such votes, the FDA doesn’t have to follow the panel’s advice, but usually does when it makes the final decision). The committee’s vote, albeit narrowly favoring approval of ecallantide, is a major step forward in Dyax’s quest to get its first drug approved for the market.

Committee members said the drug is less than perfect, but they wanted to recommend approval of the drug because treatments are needed for the serious disease, FDA spokeswoman Karen Riley writes in an e-mail. Specifically, there were concerns about allergic reactions caused by the drug.

Dyax is currently in a race get the first FDA-approved drug for the rare blood disease, which causes intense inflammation that leads to swelling of such body parts as the legs, arms and face. Dyax’s ecallantide is a protein drug intended to inhibit an enzyme that triggers the swelling in HAE patients. The FDA has told ViroPharma, headquartered in Exton, PA, that it would respond to that firm’s bid to gain approval of its competing drug by June 3. Shire, the Ireland-based drug firm, is also in the hunt for FDA approval of its drug for the disease, and the company began European sales of the treatment last year.

Hereditary angioedema affects an estimated 10,000 patients worldwide, providing Dyax with a tiny market. But the biotech company aims to follow in the footsteps of other firms such as Cambridge, MA-based biotechs Genzyme (NASDAQ:GENZ) and Shire Human Genetic Thereapies, both of which have found ways to charge high prices for life-saving therapies for rare diseases.