Comparative Assessment of the Incidence and Severity of Tardive Dyskinesia in Patients Receiving Aripiprazole or Haloperidol for the Treatment of Schizophrenia: A Post Hoc Analysis

Del D. Miller, Pharm.D., M.D.; James M. Eudicone, M.S.; Andrei Pikalov, M.D., Ph.D.; and Edward Kim, M.D., M.B.A.

Objective: To comparatively assess the incidence of tardive dyskinesia in patients with schizophrenia receiving either aripiprazole or haloperidol.

Method: Data from 2 controlled, long-term trials of subjects meeting DSM-IV criteria for schizophrenia treated with aripiprazole (N = 861, 20-30 mg/day) or haloperidol (N = 433, 5-10 mg/day) were analyzed. The primary outcome measure was the rate of new-onset tardive dyskinesia. The analysis was limited to patients without baseline tardive dyskinesia. There were no significant differences between treatment groups in demographic or disease characteristics. The Abnormal Involuntary Movement Scale (AIMS) and Research Diagnostic Criteria for tardive dyskinesia were used to define the comparative incidence rates of long-term treatment-emergent tardive dyskinesia.

Results: A significantly lower percentage of aripiprazole-treated patients developed new-onset tardive dyskinesia compared with haloperidol-treated patients (p < .0001). The annualized rate of treatment-emergent tardive dyskinesia was significantly lower in aripiprazole-treated versus haloperidol-treated patients. In patients without a baseline diagnosis of tardive dyskinesia, aripiprazole significantly improved AIMS scores compared with haloperidol (p <= .0001).

Conclusion: These findings support the potential for a significantly lower risk of tardive dyskinesia with aripiprazole than with haloperidol among patients requiring maintenance antipsychotic treatment.

(J Clin Psychiatry 2007;68:1901-1906)

Received Jan. 3, 2007; accepted Aug. 28, 2007. From the Department of Psychiatry, University of Iowa, Carver College of Medicine, Iowa City (Dr. Miller); Bristol-Myers Squibb, Plainsboro, N.J. (Dr. Kim and Mr. Eudicone); and Otsuka America Pharmaceutical, Inc., Rockville, Md. (Dr. Pikalov).

Editorial support provided by Maria Soushko, Ph.D., Phase Five Communications, Inc.; funding provided by Bristol-Myers Squibb.

Dr. Miller has been a consultant to Bristol-Myers Squibb, Pfizer, and ACADIA; has received grant/research support from Pfizer; and has received honoraria from Bristol-Myers Squibb, Pfizer, and Janssen. Dr. Kim and Mr. Eudicone are employees of Bristol-Myers Squibb. Dr. Pikalov is an employee of Otsuka America Pharmaceutical, Inc.

Corresponding author and reprints: Del D. Miller, Pharm.D., M.D., Department of Psychiatry, University of Iowa, Carver College of Medicine, #2-105 MEB, 500 Newton Rd., Iowa City, IA 52242-1000 (e-mail: del-miller@uiowa.edu).