A U.S. District Court judge has opened the door for generic drug companies to market competing versions of Wellbutrin, a popular anti-depressant drug, made by Biovail Corp. The company had been asking the Food and Drug Administration not to approve generic versions of the drug.

The Canadian drug maker’s request for a temporary restraining order and preliminary injunction against the FDA to prevent it from granting market approval of generic versions of Wellbutrin was characterized by analysts as a last-ditch effort. The judge’s decision, filed last week in U.S. District Court in Washington, D.C., clears the way for Irvine, Calif.-based Anchen Pharmaceuticals to release the first competing version of the drug.