GSK GSK plc

LONDON--GlaxoSmithKline PLC (GSK.LN) Wednesday said it began a late-stage study to evaluate the effectiveness of Eltrombopag--a drug marketed as Promacta in the U.S. and Revolade in Europe--on people with myelodysplastic syndromes, or MDS, a type of cancer in which the bone marrow doesn't make enough healthy blood cells.

The "phase three" study will examine the drug's effectiveness in boosting platelet production in combination with azacitidine, an existing medicine, GSK said.

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Write to Ed Ballard at ed.ballard@wsj.com

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