UPDATE 1-FDA staff suggests liver warning on Merck's Cancidas

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WASHINGTON Dec 4 (Reuters) - U.S. Food and Drug Administration staff said on Friday that it would recommend labeling changes for Merck's (MRK.N) Cancidas to warn of possible liver problems in children taking the fungal infection drug.

The recommendation is contained in briefing materials to be considered by the FDA's Pediatric Advisory Committee meeting on Tuesday.

The FDA staff said their review of reported adverse events showed that in seriously ill children there were some cases of abnormal liver function tests and of liver injury.

It recommended the label note that abnormalities in liver function tests have been seen in both adult and pediatric patients, and that "causal relationship to Cancidas has not been established."

They said they found no other safety issues that warranted any label changes for the drug, whose generic name is caspofungin.

Cancidas is used to treat fungal infections involving intra-abdominal abscesses, peritonitis and pleural space infections, as well as esophageal candidiasis.

The FDA staff said the drug is "generally well tolerated by patients of all ages," and that its review did not find any significant differences in the safety for children or adults.

The liver problems were found in patients under age 17, "mostly in very ill children with many competing causes for their hepatotoxicity." Cancidas is frequently used in children with other serious illness who are taking multiple drugs, which makes "an assessment of a causation challenging," the FDA staff said. (Reporting by Jackie Frank; Editing by Lisa Von Ahn) ((Company news desk in Washington, +1 202 898 8400, washington.newsroom@thomsonreuters.com))