THURSDAY, Dec. 14 (HealthDay News) -- The U.S. Food and Drug Administration has approved the first generic version of Wellbutrin XL (bupropion hydrochloride), an extended-release antidepressant sanctioned for major depressive disorder (MDD).

License to produce the generic version was granted to Anchen Pharmaceuticals Inc. of Irvine, Calif.

Last year, the brand-name drug, produced by GlaxoSmithKline, was the 21st highest-selling brand-name medication in the United States, with more than $1.3 billion in sales, the agency said in a statement.

Less-costly generic drugs are now used to fill more than 50 percent of all prescriptions, the FDA said. "Consumers and health professionals can be assured that an approved generic drug is bioequivalent to a brand-name drug and is its equal in dosage form, strength, and route of administration, quality, performance characteristics, and intended use," the agency statement added.