Enzon Appoints New Sr. Vice President of Technology.

Business/Medical Editors

PISCATAWAY, N.J.--(BUSINESS WIRE)--Aug. 29, 2000

Enzon, Inc. (NASDAQ:ENZN) announced today that Norman Hardman, Ph.D., has been appointed Sr. Vice President of Technology. Dr. Hardman will focus on the advancement of the Company's proprietary technologies, with a special emphasis on the expansion of the pipeline for the Single-Chain Antigen-Binding (SCA(r)) protein technology.

Dr. Hardman brings to Enzon 30 years experience in pharmaceutical and biotechnology research and management. Most recently, Dr. Hardman served at Onyx Pharmaceuticals, a biotechnology company focusing on novel cancer therapies. At Onyx, Dr. Hardman was responsible for research and development operations, manufacturing, and regulatory affairs. Prior to Onyx, Dr. Hardman spent three years in senior management at GeneMedicine, Inc. At GeneMedicine, Dr. Hardman managed research and development, manufacturing, and operations. Dr. Hardman also played an instrumental role in the successful merger between GeneMedicine and Megabios Corporation, which took place in 1999. From 1996 to 1997 Dr. Hardman was Head of R&D Operations at Novartis in Horsham, UK, and for the ten years prior to that, he held various research and management roles at Ciba-Geigy Pharmaceuticals in Switzerland and the UK, and led Ciba-Geigy's antibody engineering program from 1986 to 1993.

"Dr. Hardman will further enhance our senior scientific management group and work together with Jeffrey McGuire, our Chief Scientific Officer, to coordinate the focus of our core technologies and accelerate the growth of our pipeline," said Peter Tombros, Enzon's president and chief executive officer. "Norman's research and management experience, both in biotech and large pharmaceutical companies, will be a major asset to Enzon's pipeline development, particularly in the area of SCAs."

Dr. Hardman received his doctorate degree in biochemistry from the University of Manchester, UK, and has a bachelor of science degree in chemistry from the University of London. He is listed as an inventor on seven international patents and is the author of more than 70 published science articles, several in the antibody engineering field.

"Having worked previously with Norman, at GeneMedicine, I have great respect for his scientific and organizational skills," said Josef Bossart, vice president, Business Development and president, SCA Ventures. "With Norman's extensive experience in the field of antibodies, I believe he will have an immediate impact on advancing SCA Ventures' research and product development activities." SCAs are genetically engineered proteins, which possess the binding specificity and affinity of monoclonal antibodies and are designed to expand on the therapeutic and diagnostic applications possible with monoclonal antibodies.

Enzon is a biopharmaceutical company developing advanced therapeutics for life-threatening diseases through the application of its proprietary drug delivery and targeting technologies, PEG Modification, Pro Drug/Transport technology and Single-Chain Antigen- Binding (SCA(r)) protein technology. Enzon has several products in various stages of clinical development by itself and with partners, including PEG-INTRON(r) with Schering-Plough, which is in Phase III clinical trials for malignant melanoma, chronic myelogenous leukemia and in combination treatment with Schering-Plough's product REBETOL(r) for the treatment of hepatitis C. PEG-INTRON recently received approval in Europe and is awaiting marketing approval in the U.S. for the treatment of chronic hepatitis C. Enzon also has two products on the market, ONCASPAR(r), which is used to treat Acute Lymphoblastic Leukemia (ALL), and ADAGEN(r), a treatment for a form of Severe Combined Immunodeficiency Disease (SCID), commonly known as the "Bubble Boy Disease". Enzon develops and markets products on its own and through strategic alliances, which in addition to Schering-Plough Corporation include Alexion Pharmaceuticals, Inc., Baxter Healthcare Corporation, Bristol-Myers Squibb Company, Eli Lilly & Company, and Rhone-Poulenc Rorer Pharmaceuticals, Inc.

Certain statements made in this press release related to potential government approvals, market potential, commercialization and sales revenues of medical products and biologics, as well as their therapeutic applications and outcomes, are forward-looking and are made pursuant to the safe harbor provisions of the Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties, which may differ materially from those set forth in these statements. In addition, the economic, competitive, governmental, technological and other factors identified in the Company's filings with the Securities and Exchange Commission could affect such results.

This release is also available at http://www.enzon.com