Human Genome Sciences and GlaxoSmithKline PLC (GSK) announced that the U.S. Food and Drug Administration (FDA) has extended the Prescription Drug User Fee Act (PDUFA) target date for its priority review of the Biologics License Application (BLA) for BENLYSTA® (belimumab) as a potential treatment for systemic lupus erythematosus (SLE) from December 9, 2010 to March 10, 2011

ROCKVILLE, MA, USA and LONDON, UK | December 3, 2010 | Human Genome Sciences, Inc. (Nasdaq: HGSI) and GlaxoSmithKline PLC (GSK) today announced that the U.S. Food and Drug Administration (FDA) has extended the Prescription Drug User Fee Act (PDUFA) target date for its priority review of the Biologics License Application (BLA) for BENLYSTA® (belimumab) as a potential treatment for systemic lupus erythematosus (SLE) from December 9, 2010 to March 10, 2011.

After the FDA Arthritis Advisory Committee met on November 16, 2010 to consider the BENLYSTA BLA, the FDA requested some additional information from HGS, which has been submitted.

Belimumab is an investigational drug and the first in a new class of drugs called BLyS-specific inhibitors. HGS and GSK are developing belimumab under a definitive co-development and co-commercialization agreement entered into in 2006.

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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.

ABOUT HUMAN GENOME SCIENCES

The mission of HGS is to apply great science and great medicine to bring innovative drugs to patients with unmet medical needs. For more information about HGS, please visit the Company’s web site at www.hgsi.com. Health professionals and patients interested in clinical trials of HGS products may inquire via e-mail to medinfo@hgsi.comThis e-mail address is being protected from spam bots, you need JavaScript enabled to view it or by calling HGS at (877) 822-8472. HGS, Human Genome Sciences, and BENLYSTA are trademarks of Human Genome Sciences, Inc. Other trademarks referenced are the property of their respective owners.

SOURCE: HUMAN GENOME SCIENCES