Converting patients from brand-name clozapine to generic clozapine

OBJECTIVE: To evaluate safety and dosage requirements when patients taking brand-name clozapine (Clozarii, Novartis Pharmaceuticals) are converted to generic clozapine (Zenith Goldline). METHODS: In November 1999, patients at Colorado Mental Health Institute at Pueblo taking Clozaril were changed to generic clozapine. Seventeen patients had been prescribed Clozaril for three years and were:included in:the study.: Drug dosage,white blood cell (WBC) count values, and adverse drug reaction reports were compared. Data regarding patients-on the brand-name product were evaluated retrospectively for the months of November, December, January, and February during the years 1996/1997, 1997/1998, and 1998/1999. These data were compared with those from the same patients after switching to generic clozapine for the same months in 1999/2000. A one-year comparison of brand-name (1998/1999):with generic-drug (1999/2000)was also performed. Statistical analysis included a standard t-test comparing WBC values and a Brown-Forsythe test for comparing dosages; RESULTS: There were no differences between the values obtained for:the brand-name:and generic products. WBC counts for the three-year data resulted in a p value of 0.9992. There was no difference when comparing the samples one year prior to switching nd after the switch (p = 0.9991). There was no difference in dosages at three;years:or one year (p = 9.9999 and p = 0.9993, respectively). No adverse events were noted with the generic product. CONCLUSIONS: NO differences were found between the brand-name and generic clozapine groups With regard to WBC count, dosage, and adverse events. The conversion to the generic product is projected to save the pharmacy $90 000 annually. KEY WORDS: clozapine, generic.