FDA rules that Budeprion XL is not equivalent to Wellbutrin XL

Israeli generics giant Teva has withdrawn its version of the extended release tablets of antidepressant bupropion from the market. The move was prompted by an FDA investigation into whether the generic version (Budeprion XL, made by Impax and marketed by Teva) is truly therapeutically equivalent to the branded medicine (Wellbutrin XL).

Budeprion XL is a slow-release version of the antidepressant, designed to be taken once a day. The FDA study concluded that the release profile of the generic version did not match that of the branded drug well enough to be called equivalent.

However, this ruling only applies to the 300mg dose. Teva’s 150mg dose version of generic Budeprion XL is still approved as equivalent, as are several other generic versions. In the original approval, data from trials of the 150mg version were extrapolated to cover the higher dose form. According to the FDA report on the findings, ‘this methodology was based on the FDA’s guidance at the time the products were approved. The FDA has determined that this approach is no longer appropriate […], and the agency is revising its guidance to industry for how to conduct premarket bioequivalence studies in generic bupropion products.’