Washington Editor

At long last, the Antegren data are out.

Biogen Idec Inc. and Elan Corp. plc said one-year data from the Phase III AFFIRM trial met the primary endpoint of clinical relapse rate reduction. In the international study of 942 patients with relapsing-remitting multiple sclerosis, Antegren (natalizumab) reduced the rate of relapses by 66 percent compared to placebo, a statistically significant result.

The study also met all secondary endpoints. The data were presented to investigators involved in the program at a meeting over the weekend. AFFIRM is a two-year trial evaluating the product's effect on the progression of disability and the rate of relapses in multiple sclerosis.

The companies expect two-year results to be available in the first half of next year. Antegren is in regulatory review in the U.S., Europe, Canada and Australia for approval as a multiple sclerosis treatment. The FDA has granted the product priority-review and accelerated approval status.

The partners applied for approval in the U.S. in May, followed a month later by a European submission. Both were based largely on one-year data from AFFIRM and another ongoing Phase III trial, labeled SENTINEL, though the companies did not disclose data in order to complete the two-year studies and protect their integrity.

Biogen Idec, of Cambridge, Mass., and Elan, of Dublin, Ireland, first reported such plans earlier this year. Due to filing on one-year data, it has been assumed by most in the industry the data were strongly positive. (See BioWorld Today, Feb. 19, 2004.)

SENTINEL is evaluating the combination of Antegren and Avonex (Interferon beta-1a, also from Biogen Idec) compared with Avonex alone in 1,200 patients with relapsing-remitting multiple sclerosis.

Antegren, humanized monoclonal antibody, is designed to inhibit the migration of immune cells into tissues in which they might cause or maintain inflammation. The product is the first alpha-4 integrin antagonist in the new selective adhesion molecule inhibitor class. The partners also are collaborating on its development for Crohn's disease and rheumatoid arthritis.

On Monday, Biogen Idec's stock (NASDAQ:BIIB) lost 46 cents to close at $60.40. Elan's shares (NYSE:ELN) gained $1.12 to close at $29.