Does therapeutic equivalence follow bioequivalence? A randomized trial to assess clinical effects after switching from Clozaril to generic clozapine (gen-clozapine)

J Clin Pharmacol. 2010 May;50(5):531-5. doi: 10.1177/0091270009347871. Epub 2010 Jan 20.

Abstract

This study prospectively assessed outcomes in a group of patients who were randomly switched from Clozaril to generic clozapine (Gen-Clozapine). The authors examined data from rating scales administered before the switch and at points after the switch. There were no statistically significant differences between the groups on any baseline measures, including psychiatric status and dose of medication. In the group of patients who were switched to the generic formulation, there was a significant increase in Global Assessment Scale scores by the end of the 6-month monitoring period. In the group of patients who remained on Clozaril, a significant decrease in the 32-item Behavior and Symptom Identification Scale scores was found at the end of the monitoring period. The results of this study suggest that clinical equivalence indeed followed bioequivalence when switching from Clozaril to Gen-Clozapine.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antipsychotic Agents / administration & dosage*
  • Antipsychotic Agents / pharmacokinetics
  • Antipsychotic Agents / therapeutic use
  • Clozapine / administration & dosage*
  • Clozapine / pharmacokinetics
  • Clozapine / therapeutic use
  • Drugs, Generic / administration & dosage*
  • Drugs, Generic / pharmacokinetics
  • Drugs, Generic / therapeutic use
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prospective Studies
  • Psychiatric Status Rating Scales
  • Schizophrenia / diagnosis
  • Schizophrenia / drug therapy*
  • Schizophrenic Psychology
  • Single-Blind Method
  • Therapeutic Equivalency
  • Treatment Outcome

Substances

  • Antipsychotic Agents
  • Drugs, Generic
  • Clozapine