SAN DIEGO, June 3, 2002 -- La Jolla Pharmaceutical Company (Nasdaq: LJPC) announced today that it has appointed Kenneth R. Heilbrunn, M.D. to the position of Vice President of Clinical Development. Dr. Heilbrunn will oversee clinical research, biostatistics and medical affairs for the Company's ongoing Phase III clinical trial of LJP 394 for the treatment of lupus kidney disease and its Phase I/II trial of LJP 1082 for the treatment of antibody-mediated thrombosis.

"Dr. Heilbrunn brings 14 years of experience managing clinical development programs in therapeutics, biologics and devices," said Steven B. Engle, Chairman and CEO. "Dr. Heilbrunn has worked with several branches of the FDA, including the Cardio-Renal and Pulmonary divisions of the Center for Drug Evaluation and Research, the Center for Biologics Evaluation and Research and the Center for Devices and Radiological Health."

Dr. Heilbrunn most recently served as Vice President of Clinical Research at Advanced Tissue Sciences, where he was responsible for the multicenter Phase III pivotal trial and FDA approval of Dermagraft®, a bioengineered human tissue. Dr. Heilbrunn previously served as Vice President of Medical Affairs at Hepatix; Staff Vice President of Medical Affairs at C.R. Bard, a $1 billion manufacturer and developer of healthcare products and equipment for vascular, oncology and urology specialties; and Medical Affairs Director for Cardiovascular and Pulmonary Drugs at Ciba-Geigy Pharmaceuticals Division, where he participated in the launch of the nicotine patch, Habitrol®, and the antihypertensive drug, Lotensin®. Prior to Ciba-Geigy, Dr. Heilbrunn served as Staff Internist and Director of the Critical Care unit at the 31st Tactical Air Force Hospital. Dr. Heilbrunn completed his residency in internal medicine at Baystate Medical Center in Springfield, Mass. after receiving his M.D. from New York Medical College and his B.A. from Brown University.

La Jolla Pharmaceutical Company is a biotechnology company leading the development of therapeutics for antibody-mediated autoimmune diseases afflicting several million people in the United States and Europe. The Company is conducting a Phase III trial of LJP 394 in patients with lupus kidney disease, a leading cause of sickness and death in these patients. The Company is also conducting a Phase I/II trial of LJP 1082 for the treatment of antibody-mediated thrombosis, a condition in which patients suffer from recurrent stroke, deep-vein thrombosis and other thrombotic events. The Company's common stock is traded on The Nasdaq Stock Market under the symbol LJPC. For more information about the Company, visit our Web site: http://www.ljpc.com. Patients interested in the Phase III lupus trial may call 1-800-30-LUPUS for information.

Except for historical statements, this press release contains forward-looking statements involving significant risks and uncertainties, and a number of factors, both foreseen and unforeseen, could cause actual results to differ materially from our current expectations. Our analyses of clinical results of LJP 394, our drug candidate for the treatment of systemic lupus erythematosus ("lupus"), and LJP 1082, our drug candidate for the treatment of antibody-mediated thrombosis ("thrombosis"), are ongoing and future analyses could result in a finding that these drug candidates are not effective in large patient populations, do not provide a meaningful clinical benefit or may reveal a potential safety issue requiring us to develop new candidates. Our blood test to measure the binding affinity for LJP 394 is experimental, has not been validated by independent laboratories, may require regulatory approval and may be necessary for the approval and the commercialization of LJP 394. Our other potential drug candidates are at earlier stages of development and involve comparable risks. Analysis of our clinical trials could have negative or inconclusive results. Any positive results observed to date may not be indicative of future results. Even if results are promising, the U.S. Food and Drug Administration ("FDA") may require additional clinical trials. The Company's ability to develop and sell its products in the future may be affected by the intellectual property rights of third parties. Additional risk factors include the uncertainty of: obtaining required regulatory approvals; successfully marketing products; receiving future revenue from product sales or other sources such as collaborative relationships; future profitability; the need for additional financing; our dependence on patents and other proprietary rights; FDA approval of our manufacturing facilities; the increase in capacity of our manufacturing capabilities for possible commercialization; and our lack of marketing experience. Readers are cautioned to not place undue reliance upon forward-looking statements, which speak only as of the date hereof, and we undertake no obligation to update forward-looking statements to reflect events or circumstances occurring after the date hereof. Interested parties are urged to review the risks described in our other reports and registration statements filed with the Securities and Exchange Commission from time to time, including the report on Form 10-K for the year ended December 31, 2001.