Pharmaceuticals company GlaxoSmithKline LPC (GSK.LN) Thursday said it has signed a deal to supply the U.K. government with 10.6 million doses of influenza treatment Relenza to use if a flu pandemic strikes.

Precise financial terms are confidential, although a spokesman for GlaxoSmithKline said it is worth in excess of GBP100 million to the Brentford, England-based drug maker. He added the company is providing the doses at a discount to its normal price.

The U.K. government already has substantial stockpiles of Roche Holding AG's (ROG.VX) rival medicine Tamiflu. But the European Medicines Agency recommended governments don't rely on just one treatment because of emerging evidence of the bug's resistance, and the U.K. has followed that advice, GlaxoSmithKline said.

Following the deal, the U.K., like France, now has a big enough stockpile to treat 50% of its population in the event of a serious flu pandemic.

At 1333 GMT, shares in GlaxoSmithKline were down 23.5 pence, or 1.9%, at 1,232 pence, outperforming a lower FTSE-100 index, down 2.1%.

Company Web site: www.gsk.com

-By Jason Douglas, Dow Jones Newswires; 44-20-7842-9272; jason.douglas@dowjones.com

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