Washington Editor

Biogen Idec Inc. and partner Elan Corp. plc gained value Wednesday after telling Wall Street they intend to file the Antegren application for multiple sclerosis based on one-year data, as opposed to waiting for the traditional two-year data set to be completed.

Biogen Idec's stock (NASDAQ:BIIB) jumped $8.97 Wednesday, or 20.3 percent, to close at $53.23. Elan's stock (NYSE:ELN) rose $3, or 34.1 percent, close at $11.80.

The partners expect to submit the biologics license application for Antegren (natalizumab) as a treatment for multiple sclerosis in mid-2004. The companies said once it is filed and accepted they would have better insight into the pending action schedule, particularly regarding whether the BLA would be classified as a priority review.

The BLA will be based on two Phase III studies known as Affirm and Sentinel. Although both trials are two-year, randomized, multicenter, placebo-controlled, double-blind studies scheduled to be finished in the first quarter of 2005, the companies will plan the filing on the one-year data, Amy Brockelman, spokeswoman for Cambridge, Mass.-based Biogen Idec, told BioWorld Today. The pre-specified primary endpoint at one year is relapse rates.

However, both trials will be taken to their two-year completion, Lars Ekman, executive vice president and president of research development at Dublin, Ireland-based Elan, said on a conference call Wednesday.

The the firms made the decision to file on a single year of data following recent discussions with the FDA.

"But to protect the integrity of the trials, we are not disclosing one-year data at this point," Ekman said. "As we have said before, there are no other MS therapies on the market that have been approved with less than two years worth of data. However, based on our discussions with the FDA, we believe the one year is sufficient to support the filing."

Indeed, Mike King, managing director at Banc of America Securities LLC in New York, told BioWorld Today that the data must be compelling if the companies are willing to file early.

"Biogen knows what it is doing in this department, so the data must be positive," he said. "But I think the question is, will the FDA break its precedent of how it approves drugs for MS, which is on two-year disability scores."

King added that Antegren has generated some excitement because of its novel mechanism of action. Discovered by Elan, Antegren, a humanized monoclonal antibody, is the first alpha-4 antagonist in the new selective adhesion molecule inhibitor class. The drug was designed to selectively inhibit immune cells from leaving the bloodstream and to prevent those cells from migrating into chronically inflamed tissue, which occurs in a variety of inflammatory diseases. To date, about 2,800 patients have received the product in clinical studies.

Aside from MS, the partners believe Antegren might be useful in Crohn's disease, rheumatoid arthritis (RA) or possibly other indications, Ekman said.

In fact, within the past month, the partners have released favorable information about the candidate in the other potential areas. After missing the primary endpoint in a Phase III trial of Antegren in Crohn's patients in July, the partners rebounded, conducted another Phase III and hit their target. The companies said in late January their 428-patient Crohn's Phase III trial, referred to as Enact-2 (Evaluation of Natalizumab as Continuous Therapy-2), hit its primary endpoint by maintaining a response in Crohn's patients. (See BioWorld Today, July 25, 2003, and Jan. 30, 2004.)

Days later, the companies said they filed an investigational new drug application to study Antegren in rheumatoid arthritis. A Phase II trial is on track to begin in the first half of 2004.

Meanwhile, the Phase III trials in MS march on. The 900-patient Affirm (Natalizumab Safety and Efficacy in Relapsing-Remitting MS) study will evaluate the ability of natalizumab to slow the progression of disability in MS and reduce the rate of clinical relapses. The Sentinel (Safety and Efficacy of Natalizumab in Combination with Avonex [Interferon beta-1a]) study will evaluate the effect of the combination of natalizumab and Avonex compared to treatment with Avonex alone in slowing the progression of disability and reducing the rate of clinical relapses. The primary endpoints for both Phase III two-year trials in MS are based on the Expanded Disability Status Scale and relapse rates.

Biogen Idec's Avonex was approved for MS in 1996.

The deal to develop Antegren in MS, Crohn's and RA is part of an agreement signed by Elan and Biogen (prior to Biogen's merger with Idec Pharmaceuticals Inc., of San Diego) in 2000. Financial terms were not disclosed, Brockelman said.