Results from Phase III Maintenance Trial of Antegren in Crohn ¹s Disease

[Guest guest]

Results from Phase III Maintenance Trial of Antegren in Crohn¹s Disease

ANTEGREN NATALIZUMAB DDW ENACT-2 CROHN'S SANDBORN

Description

Findings of ENACT-2 (Evaluation of Natalizumab As Continuous Therapy) will

be presented for the first time at the Digestive Disease Week (DDW) annual

meeting in New Orleans.

Newswise ‹ Elan Corporation, plc and Biogen Idec announced that in a Phase

III maintenance study, ANTEGREN® (natalizumab) maintained clinical response

and remission rates throughout six months among patients with Crohn¹s

disease (CD) who had previously achieved clinical response. Additionally, a

majority of natalizumab-treated patients who were also on chronic

corticosteroid therapy were able to withdraw from corticosteroids and

maintain response in contrast to those patients on placebo. The findings of

ENACT-2 (Evaluation of Natalizumab As Continuous Therapy) will be presented

for the first time at the Digestive Disease Week (DDW) annual meeting in New

Orleans.

Crohn¹s disease, a chronic, progressive immune-mediated disease of the

gastrointestinal tract, can cause a range of debilitating symptoms such as

severe diarrhea, cramping or abdominal pain and malnutrition. Current

treatment options for the disease are limited.

³The results of ENACT-2 suggest the potential of natalizumab as a

maintenance therapy for patients with Crohn¹s disease,² said J.

Sandborn, MD, professor of medicine at the Mayo Medical School. ³This study

demonstrated sustained clinical response and remission rates throughout six

months on natalizumab. It also showed that natalizumab may help patients

eliminate or reduce concomitant use of corticosteroids from their chronic

treatment regimen. These results and the other clinical data presented at

DDW are very exciting, and support the continued development of natalizumab

as both an induction and maintenance treatment.²

ENACT-2 STUDY FINDINGS

ENACT-2 assessed 339 natalizumab-responders from the induction study ENACT-1

(a 3-month study in patients with active CD) for the effect of natalizumab

as a maintenance therapy. In the international, multi-center, double-blind,

placebo-controlled trial, patients were re-randomized to receive 300 mg of

natalizumab (n=168) or placebo (n=171), both administered monthly for 12

months. The primary endpoints of maintenance of response and remission were

assessed through six months.

Throughout six months of treatment with natalizumab, 61 percent of patients

(103/168) continued to respond to therapy (assessed monthly) compared with

29 percent (49/170) of patients on placebo (p<0.001). In addition to meeting

the primary endpoint of clinical response, 44 percent of patients (57/130)

maintained clinical remission versus 26 percent of patients (31/120) on

placebo (p=0.003). Fifty-four percent of natalizumab-treated patients

(36/67) taking corticosteroids in ENACT-1, re-randomized in ENACT-2, were

able to withdraw from corticosteroids and maintain response and remission,

compared to 25 percent (19/76) of patients on placebo (p=0.002). There were

no notable differences in the rate of serious or non-serious adverse events

between treatment groups. The most common drug-related adverse events

encountered in either treatment group in this trial were headache, fatigue

and nausea.

In addition to the presentation of ENACT-2 data, there are six abstracts

being presented at DDW on the Phase III induction study, ENACT-1. Highlights

of these data will be discussed during a joint conference call on May 19 at

11:00 a.m. Central Time. Details of the call, including playback

information, is accessible through Elan¹s homepage, www.elan.com and Biogen

Idec¹s homepage, www.biogenidec.com.

³We are encouraged by the ENACT-2 data, which continues to build the

evidence for the potential of natalizumab as a treatment for Crohn¹s

disease,² said Lars Ekman, MD, executive vice president and president,

Research & Development, Elan. ³The data suggest that natalizumab maintains

response, even in most cases when patients are withdrawn from corticosteroid

therapy. Importantly, natalizumab appears to be well tolerated in this

trial.

³Natalizumab, with its novel mechanism of action, holds promise as a therapy

with a new approach to treating Crohn¹s disease,² said Burt Adelman, MD,

executive vice president, Development, Biogen Idec. ³We look forward to its

continued development in the treatment of Crohn¹s disease.²

ABOUT ANTEGREN (NATALIZUMAB)

Natalizumab, a humanized monoclonal antibody, is the first alpha-4

antagonist in the new selective adhesion molecule (SAM) inhibitor class. The

drug is designed to inhibit the migration of immune cells into chronically

inflamed tissue where they may cause or maintain inflammation. To date,

approximately 2,800 patients have received natalizumab in clinical trials

and the safety profile continues to support further development. In placebo

controlled trials to date, in both CD and MS, the most commonly reported

adverse events in either group were headache, fatigue and nasopharyngitis.

Elan and Biogen Idec are collaborating equally on the development of

natalizumab in multiple sclerosis (MS), Crohn¹s disease (CD), and rheumatoid

arthritis (RA). Based on one-year Phase III data in MS, the companies intend

to submit applications for drug approval in the US and in Europe by the end

of the second quarter 2004. In addition, a Phase II trial for RA is

underway.

ABOUT DIGESTIVE DISEASE WEEK

Digestive Disease Week (DDW) is the largest international gathering of

physicians, researchers and academics in the fields of gastroenterology,

hepatology, endoscopy and gastrointestinal surgery. Jointly sponsored by the

American Association for the Study of Liver Diseases (AASLD), the American

Gastroenterological Association (AGA), the American Society for

Gastrointestinal Endoscopy (ASGE) and the Society for Surgery of the

Alimentary Tract (SSAT), DDW takes place May 15-20, 2004 in New Orleans,

Louisiana. The meeting showcases approximately 5,000 abstracts and hundreds

of lectures on the latest advances in GI research, medicine and technology.

ABOUT ELAN

Elan Corporation, plc is a neuroscience-based biotechnology company that is

focused on discovering, developing, manufacturing and marketing advanced

therapies in neurology, autoimmune diseases, and severe pain. Elan (NYSE:

ELN) shares trade on the New York, London and Dublin Stock Exchanges. For

additional information about the company, please visit http://www.elan.com.

ABOUT BIOGEN IDEC

Biogen Idec (NASDAQ: BIIB) creates new standards of care in oncology and

immunology. As a global leader in the development, manufacturing, and

commercialization of novel therapies, Biogen Idec transforms scientific

discoveries into advances in human healthcare. For press releases and

additional information about the company, please visit

http://www.biogenidec.com.

SAFE HARBOR/FORWARD LOOKING STATEMENTS

This press release contains forward-looking statements regarding the

potential and continued development of ANTEGREN (natalizumab) as a treatment

for Crohn¹s disease. These statements are based on the companies¹ current

beliefs and expectations. Drug development involves a high degree of risk.

Factors which could cause actual results to differ materially from the

companies¹ current expectations include the risk that unexpected concerns

may arise from additional data or analysis or that regulatory authorities

may require additional information or further studies or that the companies

may encounter other unexpected hurdles. For more detailed information on the

risks and uncertainties associated with the companies¹ drug development and

other activities, see the companies' periodic reports filed with the

Securities and Exchange Commission. The companies assume no obligation to

update any forward-looking statements, whether as a result of new

information, future events or otherwise.