LA JOLLA PHARMACEUTICAL�S NEW DRUG APPLICATION FOR LUPUS DRUG CANDIDATE RIQUENT� ACCEPTED FOR REVIEW BY FDA SAN DIEGO, February 17, 2004 -- La Jolla Pharmaceutical Company (Nasdaq: LJPC) today announced that the Company�s New Drug Application (NDA) for Riquent� 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.