title: Assessment of metabolites in bioequivalence studies: should bioequivalence criteria be applied on the sum of parent compound and metabolite?
abstract: OBJECTIVE
  The objective of this study was to demonstrate the impact of the sum of parent compound and metabolite in bioequivalence assessment.
  
  
  METHODS
  Four drugs with active metabolite were selected to assess bioequivalence. Bioequivalence criteria of 80 - 125% were applied to the parent compound, the metabolite, and the sum of parent compound and metabolite.
  
  
  RESULTS
  The results indicated that the application of 80 - 125% bioequivalence criteria to the sum of parent compound and metabolite might be misleading.
  
  
  CONCLUSIONS
  The 90% confidence interval should be applied separately to the parent compound and each metabolite.
authors.affiliation: Office of Clinical Pharmacology and Biopharmaceutics, Division of Pharmaceutical Evaluation I., Food and Drug Administration, Rockville, MD 20852, USA.
authors.forename: I
authors.initials: I
authors.lastname: Mahmood
mesh_terms: D019540:Area Under Curve; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D018491:Dopamine Agonists / Q000493:pharmacokinetics; D004311:Double-Blind Method; D004873:Ergolines / Q000493:pharmacokinetics; D006801:Humans; D013810:Therapeutic Equivalency
chemical_list: D018491:Dopamine Agonists; D004873:Ergolines; C100269:ergocryptine