A panel of drug regulators unanimously approved Gilead Sciences' ( GILD) Adefovir as a treatment for hepatitis B at a Food and Drug Administration meeting Tuesday.

The company submitted its application in March and was granted priority review, so a full FDA decision could come by the year's end. The full FDA decision usually, but not always, follows the vote of the panel.

Hepatitis B affects as much as 5% of the world's population and an estimated 1 million Americans. With approval, Pacific Growth Equities analyst Thomas Dietz estimated U.S. sales of $32 million in 2003 and U.S. and European sales of $78 million in 2004.

Dietz rates Gilead overweight, and Pacific Growth Equities makes a market in its shares. In May, Gilead signed an agreement with GlaxoSmithKline ( GSK) to market Adefovir outside the U.S.

Trading was halted in the biotech's shares Tuesday. It closed Monday at $30.86.