GlaxoSmithKlineGlaxoSmithKline plc (GSK) and Human Genome Sciences, Inc. (Nasdaq: HGSI) announced that the U.S. Food and Drug Administration (FDA) has approved Benlysta® (belimumab) for the treatment of adult patients with active, autoantibody-positive systemic lupus erythematosus (SLE) who are receiving standard therapy.

The US label includes the following limitations of use: The efficacy of belimumab has not been evaluated in patients with severe active lupus nephritis or severe active central nervous system lupus, and has not been studied in combination with other biologics or intravenous cyclophosphamide. Use of belimumab is therefore not recommended in these situations.

Moncef Slaoui, Ph.D., Chairman, GSK Research and Development, said, "The approval of Benlysta is an important step for appropriate lupus patients. Patients have been waiting for new treatment options to help manage this chronic disease. We look forward to working together with HGS to bring this new medicine to patients in the U.S."

"We and GSK are honoured to have the opportunity, with the approval of FDA, to bring Benlysta forward in the United States as the first new drug for systemic lupus in more than 50 years," said H. Thomas Watkins, President and Chief Executive Officer, HGS. "We expect to have this novel therapy available to physicians and patients within about two weeks, and our entire organisation looks forward to the positive impact we hope this new therapy will have for patients with systemic lupus."

About Benlysta
Benlysta (belimumab) is the first in a new class of drugs called BLyS-specific inhibitors. Belimumab blocks the binding of soluble BLyS, a B-cell survival factor, to its receptors on B cells. Belimumab does not bind B cells directly, but by binding BLyS, belimumab inhibits the survival of B cells, including autoreactive B cells, and reduces the differentiation of B cells into immunoglobulin-producing plasma cells. BLyS is a naturally occurring protein which was discovered by HGS in 1996.

Benlysta is made available as a lyophilised powder in single-use vials for intravenous infusion only and must be reconstituted and diluted by a healthcare professional prior to administration.

GSK submitted a Marketing Authorisation Application (MAA) for Benlysta to the European Medicines Agency (EMA) in June 2010. Regulatory applications have also been submitted and are currently under consideration in Canada, Australia, Switzerland, Russia, Brazil and The Philippines.

About the GSK/HGS collaboration
HGS and GSK are developing belimumab under a definitive co-development and co-commercialisation agreement entered into in 2006. Under the agreement, HGS had responsibility for conducting the belimumab Phase III trials, with assistance from GSK. The companies share equally in Phase III/IV development costs, sales and marketing expenses, and profits of any product commercialised under the current agreement.

GlaxoSmithKline - one of the world's leading research-based pharmaceutical and healthcare companies - is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For further information please visit www.gsk.com GSK Biopharm R&D is employing novel approaches to harness the therapeutic potential of biopharmaceuticals for the benefit of patients with serious autoimmune disease.

Human Genome Sciences exists to place new therapies into the hands of those battling serious disease.