* Agency reviewers: Clolar results hard to interpret
* FDA panel reviews drug on Tuesday

WASHINGTON - U.S. drug reviewers questioned a Genzyme Corp (GENZ.O) study meant to back wider use of the company's Clolar leukemia drug, according to documents released on Friday ahead of an advisory panel review.

Clolar is approved for treating a type of leukemia in children. Genzyme is seeking permission to promote the drug more widely to adults with acute myeloid leukemia (AML).

The lack of a randomized study combined with the heterogeneous patient population regarding AML prognostic factors makes interpretation of the study results difficult. Food and Drug Administration staff said in an analysis prepared for the panel, which meets Tuesday.

Genzyme, in a separate summary, said current treatments for adults with AML are insufficient and the company's data demonstrate clinically meaningful benefits and manageable risks for adults age 60 or older with at least one unfavorable risk factor.

The FDA will consider the advisory panel's input before deciding whether to approve Clolar for adult use. The agency usually follows panel recommendations. (Reporting by Lisa Richwine, editing by Gerald E. McCormick)