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                                                                    EXHIBIT 99.1

LJP

                                              THERAPEUTICS FOR ANTIBODY MEDIATED
LA JOLLA PHARMACEUTICAL                                DISEASES AND INFLAMMATION
COMPANY

     DATE:           September 14, 1999

     CONTACT:        Richard W. Krawiec, Ph.D., VP, Investor Relations
                     La Jolla Pharmaceutical Co.
                     Matt Kuhn, Abbott Laboratories, 847-937-2993

     RELEASE DATE:   Immediate

                     LA JOLLA PHARMACEUTICAL REGAINS RIGHTS
                TO EXPERIMENTAL LUPUS DRUG FOLLOWING TERMINATION
                  OF LICENSE AGREEMENT BY ABBOTT LABORATORIES

San Diego, CA/Abbott Park, IL, September 14, 1999 - La Jolla Pharmaceutical
Company (Nasdaq: LJPC) and Abbott Laboratories (NYSE: ABT) today announced that
Abbott has terminated its license and development agreement for the experimental
lupus drug, LJP 394. Abbott is returning all rights to the compound to La Jolla
Pharmaceutical, based on the results of analyses conducted by Abbott and an
independent third-party of a Phase II/III clinical trial of LJP 394, which
studied the compound's effects on patients with systemic lupus erythematosus,
including those with lupus nephritis.

The analyses confirmed the findings of the independent Data Monitoring Committee
that were announced on May 12, 1999: 1) that at the time the trial was stopped,
efficacy, as defined by the primary chosen endpoint, time to renal flare, was
not significantly different between the treatment and placebo groups and 2) in
patients receiving LJP 394, circulating antibodies to double-stranded DNA
(dsDNA) were reduced by a statistically significant amount in the presence of
the drug. Despite the reduction in dsDNA antibodies, no correlations with
clinical endpoints were observed.

There were no statistically significant serious safety issues, and clinical site
investigators did not report that any thrombotic events were related to drug
administration. When all reported thrombotic events, including cerebrovascular
accident, embolus, mesenteric occlusion, myocardial infarction, and
thrombophlebitis were pooled, there were more events, though the number was
still not statistically significant, in the group receiving LJP 394 than in the
placebo group.

La Jolla Pharmaceutical is continuing to analyze results from the LJP 394
clinical program. In a separate press release issued today, La Jolla
Pharmaceutical stated that while it is still evaluating the lupus results, it is
restructuring operations to reduce expenses. It will use its resources to

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accelerate the development of its antibody-mediated thrombosis Toleragen(R)
candidate and to partner its xenotransplantation drug candidate.

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 thrombosis,
a clotting disorder associated with stroke, myocardial infarction, deep-vein
thrombosis, and recurrent fetal loss, and organ rejection in
xenotransplantation. Toleragens under development by the Company are designed to
reduce the levels of disease-causing antibodies in patients suffering from these
conditions. The Company's common stock and warrants trade on The Nasdaq Stock
Market under the symbols: LJPC and LJPCW, respectively. For more information
about the Company, visit our web site: http://www.ljpc.com.

Abbott Laboratories is a global, diversified health care company devoted to the
discovery, development, manufacture and marketing of pharmaceutical, diagnostic,
nutritional and hospital products. The company employs 56,000 people and markets
its products in more than 130 countries. In 1998, the company's sales and net
earnings were $12.5 billion and $2.3 billion, respectively, with diluted
earnings per share of $1.51. Abbott's news releases and other information are
available on the company's web site at http://www.abbott.com.

Statements regarding the analysis of results from clinical trials, as well as La
Jolla Pharmaceutical's drug candidates and drug development plans, are
forward-looking statements involving risks and uncertainties, and a number of
factors, both foreseen and unforeseen, could cause actual results to differ
materially from those anticipated. Clinical trials of LJP 394 may continue to
have negative or inconclusive results. Further, delays in continued testing of
LJP 394 and/or termination of development by the Company would result in delays
or lack of government approval to market the compound. Tolerance or the specific
inactivation of pathogenic B cells is a new technology that has not been proven,
and the development of LJP 394 involves many risks and uncertainties, including,
without limitation, whether LJP 394 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 drug candidates, none of which has
progressed to clinical trials, 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 (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 quarter ended June 30, 1999.

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