LA JOLLA PHARMACEUTICAL COMPANY
REPORTS FOURTH QUARTER 2001 FINANCIAL RESULTS

La Jolla Pharmaceutical Company (Nasdaq: LJPC), reported a net loss for the fourth quarter ended December 31, 2001 of $6.7 million or $0.19 per share (on 35.3 million weighted average shares) compared to a net loss of $3.7 million or $0.13 per share (on 29.3 million weighted average shares) for the fourth quarter of 2000. The net loss for the year ended December 31, 2001 was $24.7 million or $0.71 per share (on 34.6 million weighted average shares) compared to a net loss of $13.8 million or $0.53 per share (on 26.1 million weighted average shares) for the same period in 2000.

Research and development expenses increased to $5.9 million and $23.2 million for the three and twelve months ended December 31, 2001, respectively, compared to $3.6 million and $12.9 million for the comparable periods in 2000. The increase was primarily due to expenses associated with the Company's ongoing Phase III clinical trial of its lupus drug candidate, LJP 394, which was initiated in September 2000, and the Phase I/II clinical trial of its thrombosis drug candidate, LJP 1082, which was initiated in November 2001.

Cash, cash equivalents and short-term investments as of December 31, 2001 were $47.0 million compared to $39.9 million as of December 31, 2000. Subsequently, in January 2002, the Company sold 7.0 million shares of its common stock in a private placement for net proceeds of approximately $48.4 million. During 2001, the Company completed a private placement financing for net proceeds of approximately $33.1 million.

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, including, without limitation, statements regarding the analysis of results from pre-clinical and clinical studies as well as La Jolla Pharmaceutical's drug candidates and drug development plans. These forward-looking statements involve risks and uncertainties, and a number of factors, both foreseen and unforeseen, could cause actual results to differ materially from those anticipated. Previously announced clinical results for LJP 394 are derived from a trial that was terminated prior to completion, and certain data are incomplete. The Company's blood test to measure binding affinity for LJP 394 is experimental and has not been validated by independent laboratories. Tolerance, or the specific inactivation of pathogenic B cells, is a new technology that has not been proven. The Company's ability to develop and sell its products in the future may be affected by the intellectual property rights of third parties. Future clinical trials of the Company's drug candidates may have negative or inconclusive results. Future clinical trials of the Company's drug candidates may not support results of pre-clinical or other prior trials and clinical trials of LJP 394 for treating lupus or LJP 1082 for treating antibody-mediated thrombosis and may reveal a potential safety issue requiring the development of new candidates. Any delays in testing of the Company's drug candidates or termination of development by the Company would result in delays or lack of government approval to market the compounds. The development of drug candidates involves many risks and uncertainties, including, without limitation, whether the drug can provide a meaningful clinical benefit, and any positive results observed to date may not be indicative of future results. La Jolla Pharmaceutical's other potential drug candidates involve comparable risks. Interested parties are urged to review the risks detailed from time to time in La Jolla Pharmaceutical Company's Securities and Exchange Commission filings, including the report on Form 10-K for the year ended December 31, 2000.