La Jolla Pharmaceutical Company Releases Data Indicating GCS-100 May Improve Renal Function

SAN DIEGO, CA--(Marketwired - May 23, 2013) - La Jolla Pharmaceutical Company (OTCBB: LJPC) (“La Jolla” and “Company”), a leader in the development of therapeutics targeting galectin proteins, released data today detailing the ability of lead product candidate GCS-100 to improve renal function. The retrospective analysis details the positive effect that GCS-100 treatment had on the estimated glomerular filtration rate (“eGFR”) in patients with poorly functioning kidneys. The eGFR is measured by a blood test that describes the rate at which fluid is filtered through the kidneys. GCS-100 is being developed as a treatment for Chronic Kidney Disease (“CKD”), with a Phase 2a trial expected to begin soon. A presentation of the newly released data can be found on the Company’s website. In addition, LifeSci Advisors has published a detailed note explaining the data that can be downloaded by visiting lifesciadvisors.com/clients/lajolla.

George Tidmarsh, M.D., Ph.D., President and Chief Executive Officer of La Jolla, said, “This retrospective analysis emphasizes the fact that GCS-100 treatment in patients with reduced renal function have improvement in estimated glomerular filtration rate. This analysis supports the upcoming Phase 2a trial of GCS-100 in CKD, which we hope will confirm the effect.”

About Chronic Kidney Disease

Chronic kidney disease (“CKD”) currently affects 14% of Americans or approximately 49 million people. The United States Renal Data System, 2012 Annual Data Report, states that in 2010, costs for CKD reached $41 billion for Medicare alone. Overall per person per year costs for CKD were estimated at $22,323 for Medicare patients of age 65 and older and $13,395 for patients of age 50-64. Patients with CKD may progress to end-stage renal disease (“ESRD”). According to the National Institute of Diabetes and Digestive and Kidney Diseases as of 2008, there were 547,982 individuals in the US under treatment for ESRD and 88,630 deaths per year from ESRD.

About GCS-100

GCS-100 is a complex polysaccharide that has the ability to bind to and block the effects of galectin-3. Galectin-3 is a soluble protein, over-expression of which has been implicated in a number of human diseases including cancer and chronic organ failure. The unique ability of GCS-100 to bind and sequester galectin-3 makes it an ideal candidate to prevent and treat diseases in which galectin-3 plays an important role.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company dedicated to the development of medical treatments that significantly improve outcomes in patients with life-threatening diseases. GCS-100, the Company’s lead product candidate, is a first-in-class inhibitor of galectin-3, a novel molecular target implicated in chronic organ failure and cancer. For more information on the Company please visit http://www.ljpc.com.

Forward Looking Statement Safe Harbor

This document contains forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to future events or our future results of operations. These statements are only predictions and involve known and unknown risks, uncertainties and other factors, which may cause actual results to be materially different from these forward-looking statements. The Company cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties, and other factors are described in greater detail in the Company’s filings from time to time with the U.S. Securities and Exchange Commission (“SEC”), all of which are available free of charge on the SEC’s web site http://www.sec.gov. These risks include, but are not limited to, risks relating to the development of GCS-100 and LJPC-501, the success and timing of future preclinical and clinical studies of this compound, and potential indications for which GCS-100 and LJPC-501 may be developed. Subsequent written and oral forward-looking statements attributable to the Company or to persons acting on its behalf are expressly qualified in their entirety by the cautionary statements set forth in the Company’s reports filed with the SEC. The Company expressly disclaims any intent to update any forward-looking statements.