IMPAX Receives Summary Judgment of Non-Infringement for Wellbutrin SR and Zyban ANDAs

August 26, 2002

August 26, 2002 -- IMPAX Laboratories, Inc. (Nasdaq NM: IPXL) today announced that Judge Marilyn H. Patel of the United States District Court for the Northern District of California has issued an order granting IMPAX's Motion for Summary Judgment of Non-Infringement regarding the Company's Abbreviated New Drug Applications (ANDAs) for Wellbutrin SR® and for Zyban®. GlaxoSmithKline markets Wellbutrin SR® for the treatment of depression, and markets Zyban® for the cessation of smoking. According to IMS Health, for the 12 months ended June 30, 2002, U.S. sales of Wellbutrin SR® were $1.33 billion, and U.S. sales of Zyban® were $83 million.

"We are very pleased that the U.S. District Court for the Northern District of California has granted our Motion for Summary Judgment of Non-Infringement regarding our ANDAs for Wellbutrin SR® and Zyban®," commented Barry R. Edwards, Co-Chief Executive Officer of IMPAX Laboratories. "This legal victory, combined with the recent decision of the United States District Court of New Jersey to grant our Motion for Summary Judgment and declare portions of the Schering-Plough Corporation U.S. Patent No. 4,659,716 invalid as they relate to our generic Claritin® ANDAs, has made August 2002 an excellent month for IMPAX," continued Mr. Edwards. "These decisions positively impact five of our 10 ANDA filings with Paragraph IV certification."

IMPAX currently has 17 ANDA filings pending at the FDA that address more than $9 billion in U.S. branded product sales. Ten of these filings were made under Paragraph IV of the Hatch-Waxman Amendments, and four of the 17 ANDAs have received tentative approval from the FDA.

IMPAX Laboratories, Inc. is a technology focused specialty pharmaceutical company applying its formulation expertise and drug delivery technology to the development of controlled-release and niche 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. 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: