In July 2009, HGS and GSK announced that belimumab met this primary endpoint in BLISS-52, the first of the two Phase 3 trials. Results from BLISS-76, the second Phase 3 trial, are expected in November 2009. Belimumab is being developed by HGS and GSK under a co-development and commercialization agreement entered into in August 2006.

The SLE Responder Index selected as the primary efficacy endpoint of the BLISS studies of belimumab emerged directly from exploratory analysis of the results of our Phase 2 clinical trial, said William W. Freimuth, M.D., Ph.D., Vice President, Clinical Research “ Immunology, Rheumatology and Infectious Diseases. This novel and robust index now allows clinical investigators to measure improvement in overall SLE disease activity while at the same time ensuring that the improvement is not accompanied by worsening in other disease manifestations such as organ flares. I am delighted that the validity of the endpoint has now been established with its successful prospective use in the recently completed BLISS-52 study.

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