IMPAX Comments on Purdue Pharma Lawsuit Related to Its Generic Version of OxyContin

September 26, 2002
Also Amends Filing to Include Additional Strengths

September 26, 2002 -- IMPAX Laboratories, Inc. (Nasdaq NM: IPXL) today announced that Purdue Pharma L.P. has filed a lawsuit against the Company alleging patent infringement related to IMPAX's filing of an Abbreviated New Drug Application (ANDA) for a generic version of OxyContin® (Oxycodone HCl) 40 mg. Extended Release Tablets. The lawsuit was filed in the United States District Court for the Southern District of New York. In addition, the Company announced it has amended its ANDA for the 40 mg. Tablets to include 10 mg. and 20 mg. Extended Release Tablets. IMPAX Laboratories had previously announced that the FDA had accepted the Company's ANDA for a generic version of OxyContin 80 mg. Extended Release Tablets on February 26, 2002, and that Purdue Pharma had filed suit alleging patent infringement for this formulation in April of this year.

Purdue Pharma L.P. markets OxyContin for the management of moderate to severe pain. U.S. sales of OxyContin Extended Release 40 mg. Tablets were over $500 million in the 12 months ended June 30, 2002. U.S. sales of the 10 mg. and 20 mg. Extended Release Tablets also totaled more than $500 million during the same time period. Total U.S. sales for all strengths in the same period were over $1.5 billion.

"We are pleased to have ANDAs pending with FDA covering the full range of strengths for generic OxyContin," stated Barry R. Edwards, Co-Chief Executive Officer of IMPAX Laboratories. "In our filings with the FDA, made under Paragraph IV of the Hatch-Waxman Amendments, we stated that all our generic versions of OxyContin do not infringe Purdue Pharma L.P.'s listed patents. We believe Purdue Pharma has filed its lawsuit against us as a tactic to delay the availability of lower-priced generic drugs to consumers."

IMPAX currently has 16 ANDA filings pending at the FDA that address more than $9.3 billion in U.S. branded product sales. Ten of these filings were made under Paragraph IV of the Hatch-Waxman Amendments, and four of these 16 ANDAs have received tentative approval from the FDA.

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 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: