ADDERALL XR(R) - Litigation Update.

HAYWARD, Calif. & BASINGSTOKE, England & PHILADELPHIA -- Impax Laboratories, Inc. (OTC:IPXL) and Shire plc (LSE:SHP)(NASDAQ:SHPGY)(TSX:SHQ) announce that, as published today on the Court's electronic docket, the U.S. District Court of the District of Delaware has granted the parties' request to extend until January 26, 2006 the deadline for the parties to submit the pre-trial order. The Court also agreed to stay the matters of the case pending settlement negotiations. The case is listed on the docket as Shire Laboratories Inc. v. Impax Laboratories, Inc. and is a patent infringement lawsuit involving Shire's U.S. patents Nos. 6,322,819 and 6,605,300, in connection with Impax's attempt to market a generic version of Shire's ADDERALL XR prior to the expiration of those patents.

About IMPAX Laboratories, Inc.

IMPAX Laboratories, Inc. is a technology based specialty pharmaceutical company applying its formulation expertise and drug delivery technology to the development of controlled-release and specialty generics in addition to the development of branded products. IMPAX markets its generic products through its Global Pharmaceuticals division and intends to market its branded products through the IMPAX Pharmaceuticals division. Additionally, where strategically appropriate, IMPAX has developed marketing partnerships to fully leverage its technology platform. IMPAX Laboratories is headquartered in Hayward, California, and has a full range of capabilities in its Hayward and Philadelphia facilities. For more information, please visit the Company's Web site at: www.impaxlabs.com.

About Shire PLC

Shire's strategic goal is to become the leading specialty pharmaceutical company that focuses on meeting the needs of the specialist physician. Shire focuses its business on central nervous system (CNS), gastrointestinal (GI), general products (GP) and human genetic therapies (HGT) - all being areas in which Shire has a commercial presence. The structure is sufficiently flexible to allow Shire to target new therapeutic areas to the extent opportunities arise through acquisitions. Shire believes that a carefully selected portfolio of products with a strategically aligned and relatively small-scale sales force will deliver strong results. Shire's focused strategy is to develop and market products for specialty physicians. This approach aims to deliver increased returns and lower risks. Shire's in-licensing and merger and acquisition efforts are focused on products in niche markets with strong intellectual property protection either in the US or Europe.

For further information on Shire, please visit the Company's website: www.shire.com

"Safe Harbor" statement under the Private Securities Litigation Reform Act of 1995:

To the extent any statements made in this news release contain information that is not historical, these statements are forward-looking in nature and express the beliefs and expectations of management. Such statements are based on current expectations and involve a number of known and unknown risks and uncertainties that could cause IMPAX's future results, performance or achievements to differ significantly from the results, performance or achievements expressed or implied by such forward-looking statements. Such risks and uncertainties include, but are not limited to, possible adverse effects resulting from the delisting of IMPAX's stock, IMPAX's delay in filing its 2004 Form 10-K and its Form 10-Q's for the first three quarters of 2005, IMPAX's ability to obtain sufficient capital to fund its operations, the difficulty of predicting FDA filings and approvals, consumer acceptance and demand for new pharmaceutical products, the impact of competitive products and pricing, IMPAX's ability to successfully develop and commercialize pharmaceutical products, IMPAX's reliance on key strategic alliances, the uncertainty of patent litigation, the availability of raw materials, the regulatory environment, dependence on patent and other protection for innovative products, exposure to product liability claims, fluctuations in operating results and other risks detailed from time to time in IMPAX's filings with the Securities and Exchange Commission. Forward-looking statements speak only as to the date on which they are made, and IMPAX undertakes no obligation to update publicly or revise any forward-looking statement, regardless of whether new information becomes available, future developments occur or otherwise.