The U. S. Food and Drug Administration scientists expressed their concerns with data Genzyme Corp. (GENZ) seeking to get federal approval to offer the drug Clolar to elderly patients with leukemia.

FDA scientists' fears stemmed from the seven deaths caused during the clinical trials. They think that the deaths may be related to the use of the drug.

Genzyme has submitted a report to get an approval to use Clolar in patients over 60 years who suffer from acute myelid leukemia also having other unfavorable health characteristics such as blood disorder. This drug is already being used in younger patients with leukemia.

A panel of scientists sponsored by the FDA is expected to review the safety and effectiveness of this drug shortly. Genzyme's spokesperson said that the deaths during the clinical study were no more than those caused by other medication on leukemia patients.

The panel is expected to suggest whether Genzyme should conduct a controlled trial usually considered to be the most scientifically reliable study, to establish the effectiveness of the drug. Genzyme has submitted data only from a single arm study which can create confusion about the drug's effectiveness.