FDA Staff Sees Allergic-Reaction Risk With Motavizumab

U.S. Food and Drug Administration staff said they are concerned about the risk for serious allergic reactions with a proposed AstraZeneca PLC (AZN) drug designed to prevent a respiratory infection in pre-term babies.

AstraZeneca's U.S.-based MedImmune unit is seeking FDA approval of the product, motavizumab, to be administered to babies considered at high risk for developing respiratory syncytial virus or RSV, a virus that affects the lungs and can be fatal.

The company already makes a similar product that's sold as Synagis. Motavizumab is designed to be more effective than Synagis, which is also known by its generic name palivizumab.

The FDA's antiviral drug products advisory committee will review motavizumab at a June 2 meeting. The FDA released its review of the product on its website Friday.

The panel of non-medical experts is being asked to vote on whether it thinks motavizumab should be approved.

The FDA's review, however, suggests the agency thinks motavizumab should not be approved given that Synagis is already on the market.

"We clearly have a safety signal suggesting motavizumab has more significant hypersensitivity reactions than palivizumab [Synagis]," the FDA said. The agency said the product has three times as many allergic reactions as Synagis.

MedImmune, in a background document also posted to the FDA's website Friday, said motavizumab is effective in decreasing serious RSV disease in high-risk children. The company suggested that health care professionals would be able to monitor patients for allergic reactions and stop treatment if needed.

-By Jennifer Corbett Dooren, Dow Jones Newswires; 202-862-9294; [e-mail]