Ulotaront: review of preliminary evidence for the efficacy and safety of a TAAR1 agonist in schizophrenia

Ulotaront is a trace amine-associated receptor 1 (TAAR1) agonist in Phase 3 clinical development for the treatment of schizophrenia. Ulotaront was discovered through a unique, target-agnostic approach optimized to identify drug candidates lacking D2 and 5-HT2A receptor antagonism, while demonstrating an antipsychotic-like phenotypic profile in vivo. The mechanism of action (MOA) of ulotaront is thought to be mediated by agonism at TAAR1 and serotonin 5-HT1A receptors. Ulotaront has completed two Phase 2 trials (4-week acute study and 26-week open-label extension) which led to Breakthrough Therapy Designation from the US Food and Drug Administration for the treatment of schizophrenia. In the double-blind, placebo-controlled, acute study, ulotaront was associated with significant (p < 0.001) improvement in Positive and Negative Syndrome Scale (PANSS) total score (effect size [ES]: 0.45), with improvements vs. placebo also observed across secondary endpoints. Post-hoc analyses of the acute trial revealed additional evidence to support the effect of ulotaront on negative symptoms. In the 4-week study, ulotaront was well-tolerated, with an incidence of adverse events (AEs) numerically lower compared to placebo (45.8% vs. 50.4%; with a number needed to harm [NNH] for individual ulotaront AEs all > 40). The open-label extension demonstrated further improvement across schizophrenia symptoms and confirmed the tolerability of ulotaront, with a 6-month completion rate of 67%. Based on current data, ulotaront shows potential to be a first-in-class TAAR1 agonist for the treatment of schizophrenia with a safety and efficacy profile distinct from current antipsychotics.

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

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.

C-reactive protein and response to lurasidone in patients with bipolar depression

Prior studies suggest that the inflammatory biomarker c-reactive protein (CRP) holds promise for predicting antidepressant response in patients with major depressive disorder. The objective of this study was to evaluate whether CRP might similarly predict antidepressant responses to lurasidone in patients with bipolar I depression. Serum CRP concentration was measured prior to, and following, 6 weeks of treatment in 485 outpatients with bipolar I depression. Patients were randomized to receive monotherapy with lurasidone 20-60 mg/day (N = 161), lurasidone 80-120 mg/day (N = 162) or placebo (N = 162). CRP was assessed using the wide-range CRP assay (wr-CRP). The primary efficacy endpoint was change from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) score. Mixed models and statistical interaction tests were applied to investigate the moderating effects of pre-treatment wr-CRP on clinical endpoints. CRP was evaluated as a log-transformed continuous variable and by clinically-relevant cut-points. Increasing pre-treatment wr-CRP level predicted a larger overall antidepressant response to lurasidone, as well as an increased response for a number of individual depressive symptoms. These moderating effects of pre-treatment wr-CRP remained significant after adjustment for potential confounds (e.g. baseline BMI and weight change). Treatment with lurasidone did not affect serum concentrations of CRP compared to placebo during the study. Elevated CRP level prior to treatment was associated with an enhanced clinical response to lurasidone in patients with bipolar I depression. If confirmed in future studies, CRP may represent a clinically useful diagnostic and predictive biomarker supporting a precision medicine approach to the treatment of bipolar depression.