FDA Update: Budeprion XL 300mg Not Therapeutically Equivalent to Wellbutrin XL 300mg

The FDA has reviewed new data that indicate Budeprion XL 300mg (bupropion HCl extended-release tablets; Impax Laboratories), marketed by Teva, is not therapeutically equivalent to GlaxoSmithKline's Wellbutrin XL 300mg

The FDA has changed the therapeutic equivalence rating for this product in the Agency's Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) from AB to BX, signifying that Budeprion XL 300mg fails to demonstrate therapeutic equivalence to Wellbutrin XL 300mg.  Impax has requested that the FDA withdraw approval of Budeprion XL 300mg extended-release tablets.  Impax and Teva have stopped shipping the product and are issuing detailed information to their customers. 

The data comes from a FDA-sponsored bioequivalence study comparing Budeprion XL 300mg to Wellbutrin XL 300mg.  This study was conducted in 24 healthy adults and was designed to measure both the rate and the extent of release of bupropion into the blood.  Study results became available in August 2012, and it showed that Budeprion XL 300mg tablets failed to release bupropion into the blood at the same rate and to the same extent as Wellbutrin XL 300mg. 

This announcement applies only to Budeprion XL 300mg manufactured by Impax and marketed by Teva.  It does not affect the Impax/Teva Budeprion 150mg product or generic bupropion products made by other manufacturers.

FDA did not conduct bioequivalence studies of the other four generic versions of Wellbutrin XL 300mg.  The FDA did, however, ask the other manufacturers – Anchen, Actavis, Watson, and Mylan – to conduct their own studies to assess the bioequivalence of their 300mg extended-release bupropion tablets to Wellbutrin XL 300mg.  FDA has asked these companies to submit the data from those studies no later than March 2013. 

Patients taking Budeprion XL 300 mg as a substitute for Wellbutrin XL 300 mg should talk with their health care professionals if they have questions about taking this medication.

For more information visit www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm322161.htm.