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Gilead Sciences to buy YM Biosciences for $510M

NEW YORK (AP) -- HIV drug maker Gilead Sciences Inc. said Wednesday it will pay about $510 million to buy drug developer YM BioSciences Inc.

Gilead said it will pay $2.95 per share for YM, a premium of 81 percent to the closing price of the company's shares on Tuesday. Shares of YM BioSciences rose $1.25, or 77 percent, to $2.88 in afternoon trading. Earlier the stock traded at a 52-week high of $2.92.

Gilead said YM BioScience's most advanced drug is a possible treatment for blood diseases, inflammatory disorders, and certain cancers. It said YM recently reported positive results from a study of that drug, CYT387, as a treatment for the bone marrow disorder myelofibrosis. Gilead said it expects to start a late-stage study of the drug as a treatment for myelofibrosis in the second half of 2013.

The Foster City, Calif., company said it expects the deal to close in the first quarter of 2013, subject to approval by shareholders of YM BioSciences, which is based in Mississauga, Ontario.

Gilead's approved drugs include the HIV treatments Atripla, Truvada, Virea, and Stribild. In January it bought hepatitis C drug developer Pharmasset for $11.1 billion.

Gilead Sciences shares rose 27 cents to $76.61 in afternoon trading.