NEW YORK (CNN/Money) - In a decision that came as a surprise to analysts, an FDA advisory panel Wednesday recommended Revlimid, a drug that enhances the activity of immune cells, for approval.

The panel voted 10-5 in support of Revlimid, also known as lenalidomide, a treatment for patients with transfusion-dependent anemia stemming from myelodysplastic syndromes, which is a group of blood and bone marrow disorders. The drug, produced by Celgene Corp., is designed to enhance the body's immune system and is considered by some analysts to be a potential blockbuster.

The Food and Drug Administration follows the advice of its advisory panels most of the time, and is expected to make a decision on Oct. 7.

"Their final vote for full approval was a bit of a surprise," said Derek Taller, an analyst for Cathay Financial who had rated Celgene "sell" based on the expectation of a negative vote. Following the vote, Taller said Celgene's stock had "tremendous upside potential."

Trading on Celgene Corp. (down $52.71 to $0.20, Research), a biotech based in Summit, N.J. with about $400 million in 2004 sales, was halted Wednesday morning. The company's top-selling product is Thalomid, a treatment for disfiguring skin sores from leprosy.

Taller and Cathay Financial do not own Celgene stock.