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GSK update on FDA review of Promacta® (eltrombopag)

Philadelphia, PA June 20, 2008 – GlaxoSmithKline [NYSE: GSK] today announced that the United States Food and Drug Administration has extended the priority review period for PROMACTA^® (eltrombopag) for the short-term treatment of previously treated patients with chronic idiopathic thrombocytopenic purpura, as they require more time to review the application.  The Prescription Drug User Fee action date has been extended to September 19, 2008.  

On May 30, the Oncology Drugs Advisory Committee unanimously voted, 16-0, that eltrombopag demonstrated a favorable risk-benefit profile for the short-term treatment of patients with chronic idiopathic thrombocytopenic purpura, or ITP.   

GSK will continue to work with the FDA towards the approval of eltrombopag in order to provide physicians and chronic ITP patients with a novel option for treating this difficult disease. 

About Promacta^® (Eltrombopag)

Eltrombopag, a novel oral thrombopoeitin (TPO) receptor agonist, if approved, would be the first oral short-term treatment of previously treated patients with chronic ITP to increase platelet counts and reduce or prevent bleeding.  In the pivotal studies, the most common adverse events observed in patients taking eltrombopag were headache, common cold, and nausea.

About GlaxoSmithKline

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 company information, visit GlaxoSmithKline at www.gsk.com.

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