Rapid Versus Conventional Initiation of Quetiapine in the Treatment of Schizophrenia: A Randomized, Parallel-Group Trial

Objectives: The primary objective of this study was to compare the safety and tolerability of a rapid initiation of quetiapine with the conventional initiation approved by the U.S. Food and Drug Administration (FDA). The secondary objectives included assessment of the efficacy of a rapid initiation of quetiapine compared with a conventional initiation approved by the FDA.

Method: Patients with acute schizophrenia were randomly assigned in a 3:1 ratio to the rapid-initiation group (200 mg on day 1, 400 mg on day 2, 600 mg on day 3, and 800 mg on day 4) or to the conventional-initiation group (50 mg on day 1, 100 mg on day 2, and increased in 100 mg/day increments to reach 400 mg on day 5). The tolerability measures were Barnes Akathisia Scale (BAS) and Simpson-Angus Scale (SAS) as well as all adverse events at day 1, 2, 3, 4, 5, 6, and 7 and at day 14. Standard efficacy measures were administered at baseline, day 1, day 4, day 5, day 7, and day 14. These measures consisted of the Positive and Negative Syndrome Scale (PANSS), PANSS-Excited Component (EC), and Clinical Global Impressions-Severity of Illness (CGI-S) scale.

Results: Forty patients were randomly assigned to treatment. The mean (SD) dose of quetiapine at study end point was 763.3 (106.6) and 600.0 (249.4) mg/day in the rapid-initiation group and conventional-initiation group, respectively. The most common side effects were sedation and dizziness, with no significant differences in frequency between groups. Only 2/30 patients from the rapid-initiation group discontinued treatment due to an adverse event (both for sedation), and 1/10 patients from the conventional-initiation group discontinued before receiving quetiapine. Neither serious adverse events nor differences between groups in vital signs, laboratory assessments, ECG measures, or weight changes were reported. Rapid initiation of quetiapine was generally well-tolerated and was associated with a faster onset of action than conventional initiation as measured by improvement in psychotic symptoms at days 4 and 5.

Conclusion: This study may offer preliminary evidence for tolerability and effectiveness in rapid dose initiation of quetiapine in the treatment of schizophrenia.