AMERICAN BIOGENETIC SCIENCES, INC. ANNOUNCES A PROGRAM TO ACCELERATE DEVELOPMENT OF ABS-205 FOR TREATMENT OF ALZHEIMER'S DISEASE

ABS-205 To Be Developed As Single Isomer

Copiague, New York, June 5, 2000 - American Biogenetic Sciences, Inc. (ABS) (OTCBB:MABA) announced today its plans to initiate an intensive program to accelerate the development of ABS-205 -- a cognition enhancer for the treatment of Alzheimer's disease. The company is in ongoing licensing discussions with interested pharmaceutical companies which have the ability to complete development and market this promising patented compound.

The near term efforts will focus on the synthesis and evaluation of the optical isomers of ABS-205, a strategy proven successful in generating more active pharmaceutical compounds. ABS has previously utilized this technique in the Chiral separation of its novel neuroscience compound, ABS-103R, now licensed to Abbott Laboratories (NYSE:ABT), for worldwide development, marketing and distribution. The separated isomers are to be tested for their cognition-enhancing properties in established animal models of learning and memory including an evaluation of the cognition-enhancing ability of ABS-205 in aged animals. This study has received support from the Institute for the Study of Aging, a non-profit foundation based in New York City and dedicated to improvement in quality of life for the elderly.

In a separate series of experiments aimed at evaluating ABS-205 isomers to reduce the production of amyloid (a protein fragment toxic to nerve cells) the investigators will be utilizing a transgenic mouse model of the Alzheimer's disease state.

The strategic development program will combine the extensive experience of Professor Ciaran M. Regan, Professor of Pharmacology, University College Dublin, the recent recipient of the Royal Irish Academy Award in Pharmacology & Toxicology 2000, and Professor Heinz Nau, Chairman of the Department of Food Toxicology, University of Hannover, Germany. Professor Nau's most recent successes include the discovery and pre-clinical development of the ABS-103R for the treatment of epilepsy, manic depression and the prevention of migraine headache.

Commenting on this ABS intensive research initiative, Ms. Ellena Byrne, Executive Vice President of ABS, and Director of the ABS Global Scientific Network said "Two of our most distinguished collaborators in the ABS Global Scientific Network, Professor Regan and Professor Nau have joined forces to accelerate this promising novel drug-candidate for the treatment of Alzheimer's disease and we have great confidence in their ability to bring to fruition years of research and duplicate the success of ABS-103R which was recently licensed to Abbott Laboratories."

Alzheimer's disease is a progressive neurodegenerative disease characterized by neuronal loss and brain lesions. The disease is also characterized by profound impairment of memory. The scale of the problem is increasing as the elderly segment of the population continues to grow. There are 4 million people in the U.S. today with Alzheimer's disease. (Ref: Alzheimer's Association) with an annual economic cost of $90 billion. The projected market in 2005 to treat Alzheimer's disease is estimated to by $10 billion.

American Biogenetic Sciences, Inc., based in Copiague, N.Y., researches and develops diagnostic tests for cardio-pulmonary conditions and infectious diseases, as well as new treatments for neurological disorders including epilepsy, migraine, mania, Parkinson's disease and Alzheimer's disease. ABS also seeks out new technologies and conducts research and development through its Global Scientific Network in the United States, Europe, Israel, Russia and China.

Statements in this release that are not strictly historical are "forward looking" statements within the meaning of the Private Securities Litigation Reform Act of 1995, and should be considered as subject to various risks and uncertainties that could cause actual results to differ materially from those anticipated. For further details and a discussion of these risks and uncertainties, see the Companys' Securities and Exchange Commission filings including its annual report on Form 10-K.