Bioequivalence and Therapeutic Equivalence of Generic and Brand Bupropion in Adults With Major Depression: A Randomized Clinical Trial

Clin Pharmacol Ther. 2019 May;105(5):1164-1174. doi: 10.1002/cpt.1309. Epub 2019 Jan 18.


Controversy persists about bupropion XL 300 mg generic equivalence to brand product. A prospective, randomized, double-blinded crossover in 70 adults with major depression in stable remission taking any bupropion XL 300 mg tested bioequivalence and therapeutic equivalence of available XL 300 mg products. After a 4-week lead-in on patients' existing bupropion, four 6-week phases evaluated brand and three generics. Patients were uninformed of switching. Drug overencapsulation ensured blinding. There were no differences between any generic and brand, or between generics, in peak plasma concentration (Cmax ) and area under the plasma concentration-time curve over the 24-hour dosing interval (AUC0-24 ) for racemic bupropion or major metabolites. All generics met formal bioequivalence criteria for bupropion and metabolites. There were no differences between generics and brand, or between generics, in depression symptoms or side effects, assessed by every 3-week in-person interview and daily smartphone-based self-report. There were no differences in patients' perceptions of bupropion products. Results show three bupropion XL 300 mg generic products are both bioequivalent and not therapeutically different from brand drug and each other.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Antidepressive Agents, Second-Generation / adverse effects
  • Antidepressive Agents, Second-Generation / pharmacokinetics
  • Antidepressive Agents, Second-Generation / therapeutic use*
  • Bupropion / adverse effects
  • Bupropion / pharmacokinetics
  • Bupropion / therapeutic use*
  • Cross-Over Studies
  • Depressive Disorder, Major / drug therapy*
  • Double-Blind Method
  • Drugs, Generic / adverse effects
  • Drugs, Generic / therapeutic use*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prospective Studies
  • Therapeutic Equivalency
  • Treatment Outcome


  • Antidepressive Agents, Second-Generation
  • Drugs, Generic
  • Bupropion