EXHIBIT 99.1

               LA JOLLA PHARMACEUTICAL'S NEW DRUG APPLICATION FOR
             LUPUS DRUG CANDIDATE RIQUENT(R) ACCEPTED FOR REVIEW BY
                                      FDA

SAN DIEGO, FEBRUARY 16, 2004 -- La Jolla Pharmaceutical Company (Nasdaq: LJPC)
today announced that the Company's New Drug Application (NDA) for Riquent(R) has
been accepted for review by the United States Food and Drug Administration
(FDA).

Riquent is designed to treat lupus patients with renal disease, a primary cause
of sickness and death among these patients. Riquent is the first drug candidate
specifically developed for the treatment of lupus renal disease in more than 30
years.

"The acceptance of our NDA filing is an important step for the Company. This
milestone brings us closer to achieving our goal of providing long-suffering
lupus patients with a new therapy," said Steve Engle, Chairman and CEO of La
Jolla Pharmaceutical Company.

ABOUT LUPUS

Lupus (systemic lupus erythematosus or SLE) is a chronic, life-threatening
autoimmune disease. About 90% of lupus patients are female, and many develop the
disease during their childbearing years. Approximately 50% of lupus patients
have renal disease, which can lead to irreversible kidney damage, kidney failure
and the need for dialysis. Latinos, African Americans, and Asians face an
increased risk of serious renal disease associated with lupus.

The current standard of care for lupus renal disease often involves treatment
with high doses of corticosteroids and immunosuppressive drugs that can cause
severe side effects including diabetes, hypertension and sterility, and may
leave patients vulnerable to opportunistic infections.

LA JOLLA PHARMACEUTICAL COMPANY

La Jolla Pharmaceutical Company is a biotechnology company developing
therapeutics for antibody-mediated autoimmune diseases and inflammation
afflicting several million people in the United States and Europe. The Company
is developing Riquent(R), formerly known as LJP 394, for the treatment of lupus
kidney disease, a leading cause of sickness and death in patients with lupus.
The Company is also developing 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, and is in the early stage of
developing small molecules to treat various other autoimmune and inflammatory
conditions. The Company's common stock is traded on The Nasdaq Stock Market
under the symbol LJPC. For more information about the Company, visit its Web
site: http://www.ljpc.com.

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. Forward-looking statements include those that express a plan,
belief, expectation, estimation, anticipation, intent, contingency, future
development or similar expression. Although our New Drug Application ("NDA") for
Riquent(R) has been accepted by the United States Food and Drug Administration
(the "FDA") for review, there is no guarantee that the FDA will approve Riquent
in a timely manner, or at all. Our analyses of clinical results of Riquent,
previously known as 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 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. The analysis of
the data from our Phase 3 trial of Riquent has shown that the trial did not
reach statistical significance with respect to its primary endpoint, time to
renal flare. Although our NDA for Riquent has been accepted for review by the
FDA, the results from our clinical trials of Riquent may not ultimately be
sufficient to obtain regulatory clearance to market Riquent either in the United
States or Europe, and we may be required to conduct additional clinical studies
to demonstrate the safety and efficacy of Riquent in order to obtain marketing
approval. There is no guarantee, however, that we will have the necessary
resources to complete any additional trial, that we will elect to conduct an
additional trial, or that any additional trial will sufficiently demonstrate the
safety and efficacy of Riquent. Our blood test to measure the binding affinity
for Riquent is experimental, has not been validated by independent laboratories,
may require regulatory approval, and will likely be necessary for the approval
and the commercialization of Riquent. 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. In any event,
regulatory authorities may require additional clinical trials, or may not
approve our drugs. Our ability to develop and sell our products in the future
may be adversely affected by the intellectual property rights of third parties.
Additional risk factors include the uncertainty and timing of: obtaining
required regulatory approvals, including delays associated with any approvals
that we may obtain; the clear need for additional financing; FDA approval of our
manufacturing facilities and processes; the increase in capacity of our
manufacturing capabilities for possible commercialization; successfully
marketing and selling our products; our lack of manufacturing, marketing, and
sales experience; generating future revenue from product sales or other sources
such as collaborative relationships; future profitability; and our dependence on
patents and other proprietary rights. 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 Annual Report on Form
10-K for the year ended December 31, 2002, and in other reports and registration
statements that we file with the Securities and Exchange Commission from time to
time.

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[Note: This press release was re-released on February 17, 2004 to ensure broad
dissemination of the information contained herein in light of the fact that the
initial release was published on February 16, 2004 which was a federal holiday.]