SU14. Characteristics Associated With Relapse in Patients With Schizophrenia: Post Hoc Analysis of a Randomized, Double-Blind, Placebo-Controlled, Cariprazine Relapse Prevention Trial

Abstract

Background: Relapse is common in schizophrenia; identifying characteristics associated with relapse may help improve disease management. Cariprazine, a D3/D2 receptor partial agonist, is approved in the United States for the treatment of schizophrenia. Post hoc analyses of a long-term, randomized, double-blind (up to 72 weeks), relapse prevention trial ({type:clinical-trial,attrs:{text:NCT01412060,term_id:NCT01412060}}NCT01412060) were performed to identify characteristics associated with relapse in placebo- and cariprazine-treated patients. Methods: Baseline characteristics in cariprazine-treated (3, 6, or 9 mg/d) or placebo-treated patients were evaluated in relation to relapse status. Demographic variables included age, sex, race, weight, and BMI. Psychiatric history variables included mean age at illness onset, duration of schizophrenia, duration of current episode, number of lifetime psychotic episodes, previous hospitalizations, and acute exacerbations in the past year. Baseline rating scale severity scores (eg, Positive and Negative Syndrome Scale [PANSS] and Clinical Global Impressions-Severity [CGI-S]) were evaluated. Differences in demographic and psychiatric history variables were evaluated using the Student t test (categorical variables) or Fisher exact test (continuous variables); rating scale severity scores were evaluated with 2-way ANOVA with relapse and study center as factors. Results: Relapse occurred in nearly twice as many placebo-treated (47.5%) as cariprazine-treated patients (24.8%) (hazard ratio [95% CI] = 0.45 [0.28, 0.73]). For cariprazine-treated patients who relapsed vs those who did not, significant differences were seen in baseline age (mean, 43 vs 38 y), weight (85 vs 73 kg), BMI (29 vs 26 kg/m2), and race (all, P < .05); for placebo-treated patients, there were no significant differences in demographic variables based on relapse status. In both treatment groups, patients who relapsed vs patients who did not relapse had a greater mean number of previous hospitalizations (cariprazine = 8.4 vs 4.3 [P = .0199]; placebo = 4.9 vs 2.8 [P = .0183]). Cariprazine patients who relapsed vs those who did not had longer illness duration (18.1 y vs 9.9 [P = .0005]); the number of lifetime episodes also differed by relapse status (P = .0016), with a greater percentage of relapsed patients experiencing ≥5 episodes. Baseline PANSS total score and CGI-S scores were not significantly different in relapsed vs nonrelapsed patients in either treatment group. Conclusion: While patients treated with cariprazine had a lower rate of relapse than placebo overall, the results suggest that patients who were older, heavier, or had a later stage of illness may be more prone to relapse during cariprazine treatment. In patients randomized to placebo, demographic characteristics and psychiatric history were not as meaningful in predicting relapse. Greater symptom severity at baseline did not appear to be associated with relapse.