Ecallantide, also known as DX-88 got narrow approval from Food and Drug Administration advisory panel. In the panel, six persons voted in favor of approval while 5 voted against approval. This new drug by Dyax Corp is meant for patients with hereditary angioedema (HAE), an inherited protein deficiency that causes episodes of painful swelling of the skin, intestine, mouth and sometimes the throat. The new drug is designed to suppress an enzyme called kallikrein that plays a role in the swelling.

The FDA generally follows panel recommendations. FDA will give its final decision by March 23.

FDA reviewers raised questions regarding data showing effectiveness of drug. Panel member also raised questions about allergic reactions seen in 13 percent of ecallantide patients, compared with 10 percent who got a placebo. Majority of panel members said there was not enough evidence of safety and effectiveness in patients aged 10 to 17 as Dyax is seeking approval to market the drug for patients age 10 and older.

Dr. Richard Honsinger, a panel member and physician at Los Alamos Medical Center Clinic in New Mexico said: "I'm convinced that for an orphan disease that could be fatal, we need this drug."