Elan Announces Closing of TYSABRI® Collaboration Transaction with Biogen Idec

Elan Corporation, plc (NYSE:ELN) is pleased to announce the closing today of the TYSABRI^® (natalizumab) Collaboration Transaction with Biogen Idec. The agreement was announced on February 6, 2013.

Under the terms of the agreement, Elan has received $3.25 billion in cash and will receive double digit tiered royalty payments, on all indications, for the life of the complete TYSABRI asset. For the first twelve months Elan will receive 12% royalties on in-market sales of TYSABRI, and thereafter, Elan will receive 18% royalties on in-market sales up to $2 billion and 25% royalties on in-market sales exceeding $2 billion. In 2012, in-market sales of TYSABRI were $1.6 billion.

About TYSABRI

TYSABRI is approved in more than 65 countries. TYSABRI is approved in the United States as a monotherapy for relapsing forms of MS, generally for patients who have had an inadequate response to, or are unable to tolerate, an alternative MS therapy due to the risk of progressive multifocal leukoencephalopathy (PML). In the European Union, it is approved for highly active relapsing-remitting MS (RRMS) in adult patients who have failed to respond to beta interferon or have rapidly evolving, severe RRMS.

TYSABRI has advanced the treatment of MS patients with its established efficacy. Data from the Phase 3 AFFIRM trial, which was published in the New England Journal of Medicine, showed that after two years, TYSABRI treatment led to a 68 percent relative reduction (p<0.001) in the annualized relapse rate when compared with placebo and reduced the relative risk of disability progression by 42-54 percent (p<0.001).

TYSABRI increases the risk of PML, an opportunistic viral infection of the brain which usually leads to death or severe disability. Infection by the JC virus (JCV) is required for the development of PML and patients who are anti-JCV antibody positive have a higher risk of developing PML. Factors that increase the risk of PML are presence of anti-JCV antibodies, prior immunosuppressant use, and longer TYSABRI treatment duration. Patients who have all three risk factors have the highest risk of developing PML. Other serious adverse events that have occurred in TYSABRI-treated patients include hypersensitivity reactions (e.g., anaphylaxis) and infections, including opportunistic and other atypical infections. Clinically significant liver injury has also been reported in the post-marketing setting. A list of adverse events can be found in the full TYSABRI product labeling for each country where it is approved.

As a result of the termination of the collaboration, TYSABRI will be marketed and distributed solely by Biogen Idec. For full prescribing information and more information about TYSABRI, please visit www.biogenidec.com.

About Elan

Elan is a biotechnology company, headquartered in Ireland, committed to making a difference in the lives of patients and their families by dedicating itself to bringing innovations in science to fill significant unmet medical needs that continue to exist around the world. For additional information about Elan, please visit http://www.elan.com.

About Biogen Idec

Biogen Idec uses cutting-edge science to discover, develop, manufacture and market therapies for serious diseases with a focus on neurology, immunology and hemophilia. Founded in 1978, Biogen Idec is the world's oldest independent biotechnology company. Patients worldwide benefit from its leading multiple sclerosis therapies and the company generates more than $5 billion in annual revenues. For product labeling, press releases and additional information about the company, please visit www.biogenidec.com.

The Directors of Elan accept responsibility for the information contained in this announcement. To the best of their knowledge and belief (having taken all reasonable care to ensure such is the case); the information contained in this announcement is in accordance with the facts and does not omit anything likely to affect the import of such information.

Any holder of 1% or more of any class of relevant securities of Elan or of Royalty Pharma may have disclosure obligations under Rule 8.3 of the Irish Takeover Panel Act, 1997, Takeover Rules 2007 (as amended).

Forward Looking Statements

This document contains forward-looking statements about Elan’s financial condition, results of operations, business prospects and Tysabri that involve substantial risks and uncertainties. You can identify these statements by the fact that they use words such as "anticipate”, "estimate”, "project”, "target”, "intend”, "plan”, "will”, "believe”, "expect” and other words and terms of similar meaning in connection with any discussion of future operating or financial performance or events. Among the factors that could cause actual results to differ materially from those described or projected herein are the following: the potential of Tysabri, which may be severely constrained by increases in the incidence of serious adverse events (including death) associated with Tysabri (in particular, by increases in the incidence rate for cases of PML), or by competition from existing or new therapies (in particular, oral therapies), and the potential for the successful development and commercialization of additional products, whether internally or by acquisition, especially given the separation of the Prothena business which left us with no material pre-clinical research programs or capabilities; Elan’s ability to maintain sufficient cash, liquid resources, and investments and other assets capable of being monetized to meet its liquidity requirements; the success of our development activities, and research and development activities in which we retain an interest, including, in particular, the impact of the announced discontinuation of the development of bapineuzumab intravenous in mild to moderate Alzheimer’s disease; failure to comply with anti-kickback, bribery and false claims laws in the United States, Europe and elsewhere; difficulties or delays in manufacturing and supply of Tysabri; trade buying patterns; the impact of potential biosimilar competition, whether restrictive covenants in Elan’s debt obligations will adversely affect Elan; the trend towards managed care and health care cost containment, including Medicare and Medicaid; legislation and other developments affecting pharmaceutical pricing and reimbursement (including, in particular, the dispute in Italy with respect to Tysabri sales), both domestically and internationally; failure to comply with Elan’s payment obligations under Medicaid and other governmental programs; exposure to product liability (including, in particular, with respect to Tysabri) and other types of lawsuits and legal defense costs and the risks of adverse decisions or settlements related to product liability, patent protection, securities class actions, governmental investigations and other legal proceedings; Elan’s ability to protect its patents and other intellectual property; claims and concerns that may arise regarding the safety or efficacy of Elan’s products or product candidates; interest rate and foreign currency exchange rate fluctuations and the risk of a partial or total collapse of the euro; governmental laws and regulations affecting domestic and foreign operations, including tax obligations; whether we are deemed to be an Investment Company or a Passive Foreign Investment Company; general changes in United States and International generally accepted accounting principles; growth in costs and expenses; and the impact of acquisitions, divestitures, restructurings, product withdrawals and other unusual items. A further list and description of these risks, uncertainties and other matters can be found in Elan’s Annual Report on Form 20-F for the fiscal year ended December 31, 2012, and in its Reports of Foreign Issuer on Form 6-K filed with the SEC. Elan assumes no obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.