Don’t worry though there are four companies making generic Wellbutrin. Actavis is actively working with Amgen with biosimilars as well. Actavis just recently acquired Warner Chilcott and have been combined under one company in Ireland names Actavis plc. BD
The US Food and Drug Administration (FDA) on Friday quietly announced that a second generic version of Wellbutrin XL 300 mg, a popular antidepressant manufactured by GlaxoSmithKline, has been found to not be bioequivalent to the drug and will be pulled off the market.
One of the most basic problems may have come from how the drug underwent bioequivalence testing. FDA said the product was approved at the 300 mg dose based on studies conducted using the 150 mg dose. "This methodology was based on FDA's guidance at the time the products were approved," explained FDA. The agency also noted the lower dose was used as the basis of approval due to concerns that the higher dosage could cause seizures in otherwise healthy adults, and this concern caused FDA to grant Teva/Impax a waiver for the studies—a process it refers to as "waiving up."
In a 10 October 2013 update quietly posted to its website, FDA announced that Actavis—now owned by Watson Pharmaceuticals—had submitted data that "determined that the company's generic bupropion HCl ER 300 mg tablet product is not therapeutically equivalent to Wellbutrin XL 300 mg."