Biogen Idec

Biogen Idec
Elan

Elan

February 28, 2005 07:59 ET

Biogen Idec and Elan Announce Voluntary Suspension of TYSABRI-R-


NEWS RELEASE TRANSMITTED BY CCNMatthews

FOR: BIOGEN IDEC

NASDAQ SYMBOL: BIIB

AND ELAN

NYSE SYMBOL: ELN

FEBRUARY 28, 2005 - 07:59 ET

Biogen Idec and Elan Announce Voluntary Suspension of
TYSABRI-R-

CAMBRIDGE, Mass. and DUBLIN, Ireland--(CCNMatthews - Feb 28, 2005) -

Biogen Idec (NASDAQ: BIIB) and Elan Corporation, plc (NYSE: ELN)
announced today a voluntary suspension in the marketing of TYSABRI®
(natalizumab), a treatment for multiple sclerosis (MS). The companies
are suspending supply of TYSABRI from commercial distribution and
physicians should suspend dosing of TYSABRI until further notification.
In addition, the companies have suspended dosing in all clinical trials.

This decision is based on very recent reports of two serious adverse
events that have occurred in patients treated with TYSABRI in
combination with AVONEX® (Interferon beta-1a) in clinical trials.
These events involve one fatal, confirmed case and one suspected case of
progressive multifocal leukoencephalopathy (PML), a rare and frequently
fatal, demyelinating disease of the central nervous system. Both
patients received more than two years of TYSABRI therapy in combination
with AVONEX.

The companies' actions have been taken in consultation with U.S. Food
and Drug Administration (FDA). Worldwide regulatory agencies are being
kept informed.

The companies will work with clinical investigators to evaluate
TYSABRI-treated patients and will consult with leading experts to better
understand the possible risk of PML. The outcome of these evaluations
will be used to determine possible re-initiation of dosing in clinical
trials and future commercial availability.

"Our ongoing commitment to MS patients has led us to take these steps,"
said Burt Adelman, MD, executive vice president, Development, Biogen
Idec. "Because we believe in the promising therapeutic benefit of
TYSABRI, we are working to evaluate this situation thoroughly and
expeditiously. While we work through this matter, we must place patient
safety above all other considerations."

"We are working with leading experts and regulatory agencies to
responsibly investigate these events and to develop the appropriate path
forward," said Lars Ekman, MD, executive vice president and president,
Research and Development, Elan. "Our primary concern is for the safety
of patients."

In total, approximately 3,000 patients have been treated with TYSABRI in
clinical trials of MS, Crohn's disease, and rheumatoid arthritis. To
date, the companies have received no reports of PML in MS patients
receiving TYSABRI monotherapy or in patients with Crohn's disease or
rheumatoid arthritis in TYSABRI clinical trials. Biogen Idec has
received no reports of PML in patients treated with AVONEX alone, a
product that has been on the market since 1996.

A copy of the Dear Healthcare Professional Letter regarding this matter
is available at www.tysabri.com and the companies' corporate websites.
Patients and physicians with questions should call 1-888-489-7227.

Biogen Idec will host a webcast for the media and the investment
community at 10:00 a.m. EST today. Elan will also host a webcast at
11:30 a.m. EST today. These webcasts can be accessed through the
investor relations' sections of the companies' websites.

About Biogen Idec

Biogen Idec 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 product labeling, press releases and
additional information about the company, please visit
http://www.biogenidec.com.

About Elan

Elan Corporation, plc is a neuroscience-based biotechnology company. We
are committed to making a difference in the lives of patients and their
families by dedicating ourselves to bringing innovations in science to
fill significant unmet medical needs that continue to exist around the
world. Elan shares trade on the New York, London and Dublin Stock
Exchanges. For additional information about the company, please visit
http://www.elan.com.

Safe Harbor/Forward Looking Statements

This press release contains forward-looking statements regarding the
potential for TYSABRI. These statements are based on the companies'
current beliefs and expectations, and are subject to risks and
uncertainties that could cause actual results to differ materially.
There is no assurance, for example, that the serious adverse events
discussed above were not caused by TYSABRI, that there are not or will
not be more such serious adverse events or that we will be able to gain
sufficient information to fully understand the risks associated with the
product. There is also no assurance that the companies will be able to
resume marketing and sales of TYSABRI. For more detailed information on
the risks and uncertainties associated with TYSABRI and the companies'
drug development and other activities, see the periodic and other
reports of Biogen Idec Inc. and Elan Corporation, plc 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.

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Contact Information

  • FOR FURTHER INFORMATION PLEASE CONTACT:
    Media Contacts:
    Biogen Idec
    Amy Brockelman, 617-914-6524
    or
    Elan
    Anita Kawatra, 212-407-5740 or 800-252-3526
    or
    Investor Contacts:
    Biogen Idec
    Elizabeth Woo, 617-679-2812
    or
    Elan
    Emer Reynolds, 353 1 709 4000 or 800-252-3526