M208. MEASURES OF COGNITION AND SOCIAL FUNCTIONING IN SCHIZOPHRENIA PATIENTS RECEIVING SEP-363856 (2020)

Abstract Background SEP-363856 is a novel trace amine associated receptor-1 (TAAR1)/5-HT1A agonist with no dopamine-D2/5-HT2A antagonist activity. SEP-363856 showed significant antipsychotic efficacy in patients with schizophrenia, and a safety and tolerability profile similar to placebo and consistent with a non-D2 mechanism of action. Here, we examined measures of cognition and social functioning in schizophrenia patients receiving SEP-363856. Methods Patients aged 18–40 years with an acute exacerbation of schizophrenia were randomized, double-blind (DB), to 4-weeks of flexible-dose treatment with once daily SEP-363856 (N=120; 50 or 75 mg) or placebo (N=125). Patients (N=156) entering a subsequent 26-week open-label (OL) extension study were evaluated utilizing the Cogstate Brief Battery, administered at DB baseline and week 4, and OL baseline and weeks 12 and 26. Standardized z-scores were calculated for the Cogstate composite and subscale tasks (Detection task, Identification task, One Card Learning task, One Back task). The University of California San Diego Performance Based Skills Assessment (UPSA-B) scale was assessed at the same time-points, as were the following psychiatric scales: Positive and Negative Syndrome Scale (PANSS), the Brief Negative Symptom Scale (BNSS), the Montgomery–Åsberg Depression Rating Scale (MADRS), the Clinical Global Impression Scale, severity scale (CGI-S), and the Pittsburgh Sleep Quality Index global score (PSQI-global). Pearson correlation analyses were performed between DB baseline to Week 26 change in Cogstate composite and subscale scores and Week 26 change in the psychiatric scale scores. Results Small improvements, from DB baseline to Week 26, were observed in standardized scores on the Cogstate composite (+0.29), Identification task (+0.19), Detection task (+0.28); One Card learning task (+0.33); and One Back task (+0.33). Improvement from OL baseline at Week 26 was also observed on the mean [SD] UPSA-B total score (+6.2 [11.6]). At DB baseline, there were no correlations between CogState composite score and individual test scores with any of the psychiatric scales. Week 26 improvement in the following Cogstate composite and subscale tasks were correlated with Week 26 improvement in the following psychiatric scale scores: Cogstate composite score (PANSS total, r=-0.26; BNSS total, r=-0.31; CGI-S, r=-0.30; MADRS total, r=-0.23; PSQI-global, r=-0.23); Identification task (PANSS total, r=-0.30; BNSS total, r=-0.30), Detection task (BNSS total, r=-0.30; CGI-S, r=-0.28; PSQI-global, r=-0.23); One Card learning task (MADRS total, r=-0.29); and One Back task (PANSS total, r=-0.26). Discussion During 6-months of open-label extension treatment with SEP-363856, improvement in overall functioning was observed on the UPSA-B scale; and small but consistent improvement in cognition was noted in the Cogstate composite and subscale task scores. Endpoint reduction in the severity of schizophrenia-related symptomatology (eg, on the PANSS, BNSS, MADRS, insomnia) were associated with modest correlations, in the range of 0.2 to 0.3, in cognitive performance as measured by the Cogstate composite and subscale task scores.