Abstract
Switching to Iloperidone: An Omnibus of Clinically Relevant Observations from a 12-Week, Open-Label, Randomized Clinical Trial in 500 Persons with Schizophrenia
Author(s): Leslie Citrome, Peter J. Weiden, Gus Alva, Ira D. Glick, Richard Jackson, Greg Mattingly, Farid Kianifard, Xiangyi Meng, Adam WinseckObjective: To describe secondary analyses from a 12-week, randomized, open-label trial where adult schizophrenia outpatients receiving risperidone, olanzapine, or aripiprazole were switched to iloperidone. Methods: Patients were randomized into two groups: one where the antecedent antipsychotic dose was titrated downwards to zero over 2 weeks (n=240), and the other group where the antecedent antipsychotic was abruptly stopped (n=260). Adaptations of the Clinical Global Impression scale were used to evaluate clinical changes. Other assessments included the reporting of adverse events (AEs), study discontinuation, body weight, and metabolic variables. Results: Improvement was steady throughout the study for both gradual- and immediate-switch groups starting at Week 1 and continuing through Week 12. Discontinuations due to AEs in the first 2 weeks of treatment were higher for the immediate-switch group compared with the gradual-switch group (10.8% vs. 5.4%, NNT 19, 95% CI 10–151). Fewer patients in the gradualswitch group experienced dizziness as an AE, whereas a higher percentage of patients in the immediate-switch group exhibited earlier onset of a therapeutic response within the first 2 weeks; both groups were comparable thereafter with low rates of dizziness and similar efficacy outcomes. Conclusions: Switching to iloperidone can be accomplished either with a gradual crossover or immediate discontinuation of the prior antipsychotic; however, the immediate-switch method is associated with greater proportion of initial dizziness. The observed outcomes are consistent with what has been previously reported regarding iloperidone’s favorable akathisia/EPS profile and modest impact on somnolence/ sedation, body weight, and metabolic variables.