HGS, GSK announce full presentation of BLISS-76 Phase 3 BENLYSTA trial results for SLE at EULAR 2010

Human Genome Sciences, Inc. (Nasdaq: HGSI) and GlaxoSmithKline PLC (GSK) today announced the full presentation of results from BLISS-76, one of two pivotal Phase 3 trials of BENLYSTA® (belimumab) in seropositive patients with systemic lupus erythematosus (SLE). The results will be presented today in Rome at the 2010 Congress of the European League Against Rheumatism (EULAR).

“The evidence of durability of belimumab's clinical effect over the course of five years in a long-term Phase 2 continuation study, together with the favorable safety profile observed in the study, suggests that belimumab may have potential for chronic use in the treatment of patients with seropositive SLE”

"The BLISS-76 Phase 3 results presented at EULAR extend the findings of previous studies and reinforce our belief that belimumab, assuming regulatory approval, could deliver a significant therapeutic option for seropositive patients with systemic lupus," said David C. Stump, M.D., Executive Vice President, Research and Development, HGS. "In both of its pivotal Phase 3 trials in these patients, belimumab 10 mg/kg met its primary endpoint. The efficacy of treatment with belimumab plus standard of care compared with placebo plus standard of care was superior in both studies, with overall adverse event rates for belimumab comparable to placebo."

Carlo Russo, M.D., Senior Vice President, Biopharm Development, GSK, said, "Belimumab is the first medicine developed specifically for lupus that has reached this late stage of clinical development with positive results. The BLISS-76 results presented at EULAR, taken together with the results of BLISS-52, reinforce our belief that belimumab may play an important role for patients living with lupus."

Belimumab is an investigational drug and the first in a new class of drugs called BLyS-specific inhibitors. It is being developed by HGS and GSK under a co-development and commercialization agreement entered into in 2006. GSK submitted a Marketing Authorization Application to the European Medicines Agency (EMA) on June 4, 2010, seeking approval to market belimumab in Europe for treatment of autoantibody-positive patients with SLE. On June 10, 2010, HGS announced submission of a Biologics License Application (BLA) to the U.S. Food and Drug Administration seeking approval to market belimumab in the United States. No new drug for lupus has been approved by regulatory authorities in more than 50 years.