GlaxoSmithKline Plc Monday reached an agreement with Merck for the acquisition of marketing rights for Mecavor in the United States.

Through this deal GlaxoSmithKline will make milestone and royalty payments to Merck.

The deal came amid warnings from the U.S. Food and Drug Administration (FDA) which alleges that launching of the another GlaxoSmithKline breast-cancer drug left out some important safety information.

These letters, which were part of the launch campaign for Tykerb, are misleading in that they omit and minimize the most serious and important risk information for Tykerb and selectively present efficacy information for Tykerb, thereby overstating the efficacy of the drug, the FDA said in the Nov. 21 warning letter.

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