Comparison of the effectiveness of brand-name and generic antipsychotic drugs for treating patients with schizophrenia in Taiwan

Schizophr Res. 2018 Mar:193:107-113. doi: 10.1016/j.schres.2017.06.020. Epub 2017 Jun 17.

Abstract

The purpose of this nationwide population-based study is to compare the long-term effectiveness of brand-name antipsychotics with generic antipsychotics for treating schizophrenia. We identified patients with schizophrenia who were prescribed antipsychotics from a random sample of one million records from Taiwan's National Health Insurance database, observed between January 1, 2000 and December 31, 2012. Only those with no prior use of antipsychotics for at least 180days were included. We selected patients who were prescribed brand-name risperidone (N=404), generic risperidone (N=145), brand-name sulpiride (N=334), or generic sulpiride (N=991). The effectiveness of the treatments researched in this study consisted of average daily doses, rates of treatment discontinuation, augmentation therapy, and psychiatric hospitalization. We found that compared to patients treated with generic risperidone, those treated with brand-name risperidone required lower daily doses (2.14mg vs. 2.61mg). However, the two groups demonstrated similar rates of treatment discontinuation, augmentation, and psychiatric hospitalization. On the other hand, in comparison with patients prescribed generic sulpiride, those treated with brand-name sulpiride not only required lower daily doses (302.72mg vs. 340.71mg) but also had lower psychiatric admission rates (adjusted hazard ratio: 0.24, 95% confidence interval: 0.10-0.56). In conclusion, for both risperidone and sulpiride, higher daily doses of the respective generic drugs were prescribed than with brand-name drugs in clinical settings. Furthermore, the brand-name sulpiride is more effective at preventing patients from hospitalization than generic sulpiride. These findings can serve as an important reference for clinical practices and healthcare economics for treating schizophrenic patients.

Keywords: Antipsychotics; Brand-name; Cohort study; Effectiveness; Generic; Psychosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antipsychotic Agents / classification
  • Antipsychotic Agents / therapeutic use*
  • Cohort Studies
  • Drug Utilization Review / statistics & numerical data*
  • Drugs, Generic / therapeutic use*
  • Female
  • Humans
  • Male
  • Middle Aged
  • National Health Programs
  • Risperidone / therapeutic use
  • Schizophrenia / drug therapy*
  • Schizophrenia / epidemiology
  • Statistics, Nonparametric
  • Sulpiride / therapeutic use
  • Taiwan / epidemiology
  • Treatment Outcome

Substances

  • Antipsychotic Agents
  • Drugs, Generic
  • Sulpiride
  • Risperidone