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                                                                    EXHIBIT 99.1

May 26, 1999
Richard Krawiec, Ph.D., Vice President, Investor Relations


LA JOLLA PHARMACEUTICAL EXTENDS LIFE OF WARRANTS BY ONE YEAR

San Diego, CA - May 26, 1999 - La Jolla Pharmaceutical Company (Nasdaq: LJPC)
announced today that it has decided to extend by one year the life of all
Company warrants and an option granted to the underwriter of the Company's
initial public offering to purchase additional shares of the Company's common
stock and warrants. All warrants to purchase shares of Company common stock and
the underwriter's option had been set to expire on June 3, 1999. The warrants
and underwriter's option will be exercisable at any time until June 3, 2000. The
remaining terms of the Company's public warrants (LJPCW), including the exercise
price of $3.00 per one half share, and the remaining terms of the Company's
other warrants and the underwriter's option, including exercise prices, remain
unchanged and are explained in La Jolla Pharmaceutical Company's Securities and
Exchange Commission filings on Form 10-K for the year ended December 31, 1998.

San Diego-based La Jolla Pharmaceutical Company develops disease-specific
therapeutics using its proprietary Tolerance Technology(R) for major diseases
and conditions caused by antibodies such as lupus, antibody-mediated stroke,
myocardial infarction, deep vein thrombosis, recurrent fetal loss, organ
rejection in xenotransplantation, Rh hemolytic disease, and myasthenia gravis.
Toleragens(R) under development by La Jolla Pharmaceutical are designed to
reduce the levels of disease-causing antibodies in patients suffering from these
conditions. The Company's common stock and public warrants trade on The Nasdaq
Stock Market under the symbols LJPC and LJPCW, respectively. For more
information about the Company, visit our web site: www.ljpc.com.

Some of the statements in this press release discuss future expectations,
contain projections or state other forward-looking information. These statements
involve risks and uncertainties, and a number of factors, both foreseen and
unforeseen, could cause actual results to be materially different from those
contemplated by the forward-looking statements. Interested parties are urged to
review the risks detailed from time to time in La Jolla Pharmaceutical Company's
Securities and Exchange Commission (SEC) filings, including the report on Form
10-K for the year ended December 31, 1998 and the report on Form 10-Q for the
first quarter ended March 31, 1999.

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