Dyax gets an FDA 'breakthrough' tag for its rare disease drug

Dyax CMO Burt Adelman

The FDA has conferred its coveted breakthrough-therapy designation to Dyax's ($DYAX) lead pipeline asset, an antibody designed to treat flare-ups of the rare hereditary angioedema (HAE).

Breakthrough status guarantees Dyax access to senior staff as it develops DX-2930, giving the biotech an inside track at the agency and making the treatment eligible for a shortened review process once the biotech submits it to regulators. HAE, which affects about 1 in every 50,000 people, is an inflammatory ailment that results in bouts of severe swelling.

Dyax's subcutaneous treatment, which blocks the enzyme plasma kallikrein, significantly lowered patients' average number of weekly HAE attacks compared with placebo in Phase Ib results disclosed in March. The antibody also met all of its safety, tolerability and pharmacokinetic goals, the company said, and Dyax is planning to launch a Phase II study later this year.

The injection's initial success sent Dyax's shares up more than 50% in March, and the biotech quickly capitalized with a $230 million public offering, filling its coffers to fund the next stage of DX-2930's development.

Headquartered in Burlington, MA, Dyax is working to usurp its own Kalbitor, a subcutaneous treatment for HAE attacks approved in 2009. Since that treatment's debut, rivals Shire ($SHPG) and Salix, now part of Valeant Pharmaceuticals ($VRX), have launched HAE treatments of their own, and Dyax pulls in about $65 million a year from its sole marketed therapy.

Beyond its top prospect, Dyax is looking into plasma kallikrein-related diseases beyond HAE, investigating whether its proprietary technology has a future in diabetic macular edema, inflammatory bowel disease, rheumatoid arthritis and other disorders.

"Receipt of Breakthrough Therapy designation is a key milestone for the DX-2930 development program," said Burt Adelman, the chief medical officer at Dyax. "We look forward to taking full advantage of the opportunities that Breakthrough Therapy designation allows in order to maximize the possibility of a rapid path to approval."

- read the statement (PDF)