SEP-363856 is a novel psychotropic agent without dopamine D2 receptor occupancy. Although its mechanism of action has not been fully elucidated, preclinical data suggest that agonism at trace amine receptor 1 (TAAR1) and the serotonin 5-H1A receptor contributes to its efficacy. In a double-blind (DB), placebo-controlled study, SEP−363856 demonstrated significant efficacy in the treatment of an exacerbation of schizophrenia (Koblan et al, NEJM 2020; 82:1497–1506). We present results of a 6-month extension study whose aim was to evaluate the safety and effectiveness of longer-term treatment with SEP−363856.

Patients with an acute exacerbation of schizophrenia who completed a 4-week, DB, placebo-controlled, flexible-dose (50 or 75 mg) study of SEP−363856 were given the option to enroll in an extension study in which they were treated, open-label (OL), with flexible doses (25/50/75 mg/d) of SEP−363856 for 26-weeks. The primary outcomes were safety measures; effectiveness outcomes were secondary and included the PANSS total score and the Brief Negative Symptom Scale (BNSS) total score.

A total of 193 patients completed the 4-week DB study, and 156 (80.8%) were dosed in the OL extension study and received at least one dose of SEP−363856 (safety population). Study completer rate was 66.9%; reasons for discontinuation consisted of adverse event (11.5%), withdrawal of consent (10.2%), lack of efficacy (5.1%), and other (6.4%). 15 patients experienced an SAE: schizophrenia (n=11); acute psychosis (N=1); uterine hemorrhage and suicidal ideation (N=1 each); there were no deaths in the study. Individual AEs with an incidence =2% were schizophrenia (12.2%), headache (11.5%), insomnia (8.3%), anxiety (5.1%), somnolence (4.5%), nasopharyngitis (4.5%), nausea (3.8%), irritability (3.2%), influenza (3.2%), weight decreased (3.2%), and prolactin increased (2.6%). On movement scales, minimal mean change from OL-baseline to Week 26 occurred on the Barnes total score (−0.1), AIMS total score (0.0) and SAS score (−0.1). Mean month 6 change from DB baseline in weight was −0.3 kg. No clinically meaningful median changes were observed at week 26 in metabolic laboratory parameters (total and LDL cholesterol, triglycerides, hemoglobin A1c) or in prolactin levels. During 6 months of OL treatment, one patient had an increase in QTcF =60 msec; no patients had a QTcF interval =480 msec. Treatment with SEP−363856 was associated with significant improvement from OL baseline to week 26 in PANSS total score (−22.6) and BNSS total score (−11.3).

Treatment with SEP−363856 was associated with continued improvement from open-label baseline in the PANSS total (−22.6) and BNSS total (−11.3) scores. The most frequently reported adverse events (= 5%) were schizophrenia, headache, insomnia and anxiety. SEP−363856 had minimal effects on weight, lipids, glycemic indices, prolactin, and was associated with minimal risk of extrapyramidal symptom.

Sunovion Pharmaceuticals Inc.

SEP-363856 is a novel psychotropic agent that has shown broad efficacy in animal models of schizophrenia and depression. Its antipsychotic effects appear to be mediated by agonist activity at both trace amine-associated receptor 1 (TAAR1) and 5-HT1A receptors. Notably, SEP-363856 does not bind to any dopaminergic, serotonergic (except 5-HT1A), glutamatergic, or other neuroreceptors thought to mediate the effects of currently available antipsychotics. The aim of this study was to evaluate the efficacy and safety of SEP-363856 in acutely symptomatic patients with schizophrenia.

Patients aged 18-40 years meeting DSM-5 criteria for schizophrenia (PANSS total score ≥80) were randomized, double-blind, to 4-weeks of flexible-dose SEP-363856 (50 or 75 mg/d) or placebo. Efficacy measures included the Positive and Negative Syndrome Scale (PANSS) total score (primary), PANSS subscale scores, and the Clinical Global Impressions-Severity (CGI-S) score. Change from baseline in primary and secondary measures were analyzed using a mixed model for repeated measures (MMRM) analysis.

Study treatment groups were similar at baseline: SEP-363856 (N=120; male, 64.2%; mean age, 30.0 years; PANSS total score, 101.4) and placebo (N=125; male, 63.2%; mean age, 30.6 years; PANSS total score, 99.7). Least-squares (LS) mean reduction from baseline to week 4 was significantly greater for SEP-363856 vs. placebo on the PANSS total score (-17.2 vs. -9.7; P=0.001; effect size, 0.45), PANSS positive subscale score (-5.5 vs. -3.9; P=0.019; effect size, 0.32), PANSS negative subscale score (-3.1 vs. -1.6; P=0.008; effect size, 0.37), PANSS general psychopathology subscale score (-9.0 vs. -4.7; P<0.001; effect size, 0.51), and the CGI-Severity score (-1.0 vs. -0.5; P<0.001; effect size, 0.52). Discontinuation rates for SEP-363856 vs. placebo were similar overall (21.7% vs. 20.8%) and due to an adverse event (8.3% vs. 6.4%). Change in weight, lipids, glucose and prolactin was similar in SEP-363856 and placebo groups. Adverse events occurring with an incidence ≥2% on SEP-363856 or placebo (with SEP-363856 incidence higher than placebo) were: somnolence (6.7% vs. 4.8%), agitation (5.0% vs. 4.8%), nausea (5.0% vs. 3.2%), diarrhea (2.5% vs. 0.8%), and dyspepsia (2.5% vs. 0%). The proportion of patients who reported any extrapyramidal symptom was 3.3% on SEP-363856 and 3.2% on placebo.

In this placebo-controlled study, treatment with SEP-363856, a novel psychotropic agent, was associated with statistically significant and clinically meaningful improvement in schizophrenia symptoms as demonstrated by endpoint change in PANSS total and subscale scores, and CGI-Severity scores. Safety and tolerability findings for SEP-363856 were in general similar to placebo. In particular, SEP-363856 was not associated with extrapyramidal symptoms, akathisia, or hyperprolactinemia, consistent with its non-D2 mechanism of action.

NCT02969382

Supported by funding from Sunovion Pharmaceuticals Inc.

Once-daily dosing with dasotraline, a novel dopamine and norepinephrine reuptake inhibitor, achieves stable plasma concentrations over 24 hours. This phase 3 study evaluated the efficacy and safety of dasotraline in children with attention deficithyperactivity disorder (ADHD) throughout the day, in a laboratory classroom setting (NCT02734693).

Children (6–12 years) meeting DSM-5 criteria for ADHD were randomized to 2 weeks of dasotraline or placebo (dosed daily at home at approximately 8 PM). Following an abbreviated practice day, laboratory classroom evaluations took place at baseline and on Day 15. The primary endpoint was mean change from baseline at Day 15 in ADHD symptoms, as measured by the Swanson, Kotkin, Agler, M-Flynn, and Pelham Combined Score (SKAMP-CS), obtained from the average of 7 assessments collected across the 12-hour laboratory classroom day (12–24 hours post-dose). Secondary endpoints included SKAMP scores obtained throughout the day at individual timepoints from 8 AM through 8 PM (12–24 hours post-dose), and measures of safety and tolerability.

The ITT population comprised 112 patients. Mean age was 9.5 years, 68.8% were male; 92% completed the study. Dasotraline 4 mg/day significantly improved mean SKAMP-CS versus placebo (p<0.0001, effect size 0.85) with significant effects persisting throughout the day. Mean SKAMP subscores improved significantly versus placebo (Attention p<0.0001, effect size 0.81; Deportment p<0.001, effect size 0.70). Treatment-emergent adverse events were generally mild or moderate in severity; most frequent (with dasotraline 4 mg/day; placebo) included: insomnia (19.6%; 3.6%, all terms combined), decreased appetite (10.7%; 3.6%), headache (10.7%; 8.9%), affect lability (8.9%; 7.1%), irritability (5.4%; 3.6%), postural orthostatic tachycardia syndrome (5.4%; 0%), and perceptual disturbances (5.4%; 0%).

In this 2-week, randomized, double-blind, laboratory classroom study in children with ADHD, once-daily dasotraline significantly improved ADHD symptoms (including deportment and attention), compared with placebo, and demonstrated sustained efficacyup to 24 hours post-dose. The most common adverse events were insomnia, decreased appetite, and headache.

Study sponsored by Sunovion Pharmaceuticals Inc.

Binge eating disorder (BED) is the most common eating disorder in the US, with a lifetime prevalence of 2.8%. Disturbances in reward circuitry have been implicated in its pathogenesis. Dasotraline is a novel and potent dopamine and norepinephrine reuptake inhibitor with slow absorption and a long half-life resulting in stable plasma concentrations over 24 hours with once-daily dosing. This study evaluated the efficacy and safety of flexibly-dosed dasotraline (4, 6, and 8 mg/day) vs placebo in adults with moderate to severe BED over a 12-week period (NCT02564588).

Key inclusion criteria included moderate to severe BED based on a history of ≥2 binge eating days/week for ≥6 months prior to screening, and ≥3 binge eating days for each of2 weeks prior to randomization, as documented in participant’s binge eating diary. Patients were randomized 1:1 to flexibly-dosed dasotraline (4, 6, 8 mg/day) or placebo. Theprimary endpoint was change from baseline (CFB) in the number of binge eating days per week at Week 12. Key secondary endpoints were: CFB in Clinical Global Impression–Severity (CGI-S) Scale at Week 12; CFB in Yale-Brown Obsessive Compulsive Scale Modified for Binge Eating (YBOCS-BE) at Week 12; and the percentage ofsubjects with a 4-week cessation from binge eating prior to Week 12 or end of treatment (EOT). Except for 4-week cessation, the other three variables were analyzed using amixed model for repeated measures (MMRM).

317 subjects (84% female) received ≥1 dose of study medication (mean age was 38.2 years; mean number of binge eating days per week, 4.25; mean CGI-S score, 4.5; mean BMI, 34.7). The MMRM analysis of CFB at Week 12 in the number of binge days/week yielded a significant mean difference of –0.99 (95% CI: –0.65 to –1.33; p<0.001) infavour of dasotraline (–3.74 in the dasotraline group vs –2.75 in the placebo group). All three key secondary endpoints were met at Week 12 or EOT: 46.5% of subjects in thedasotraline group achieved at least 4 consecutive weeks’ cessation from binge eating vs 20.6% in the placebo group (p<0.001); CFB in CGI-S and YBOCS-BE scores were also statistically significant in favour of dasotraline (p<0.001). The treatment-emergent adverse events (TEAEs) that occurred more frequently with dasotraline vs placebo at >2% incidence included: insomnia (44.6% vs 8.1%), dry mouth (27.4% vs 5.0%), decreased appetite (19.7% vs 6.9%), anxiety (17.8% vs 2.5%), nausea (12.7% vs 6.9%) and decreased body weight (12.1% vs 0%). Discontinuation due to AEs occurred in 11.5% of patients taking dasotraline vs 2.5% taking placebo.

In adults with moderate to severe BED, there were highly significant and clinically meaningful reductions with dasotraline vs placebo in the frequency of binge eating, global severity of illness, and obsessive-compulsive symptoms related to binge eating. These results suggest dasotraline may offer a novel, well-tolerated and efficacious treatmentfor BED.

Study sponsored by Sunovion Pharmaceuticals Inc.

Once-daily dosing with dasotraline, a novel dopamine and norepinephrine reuptake inhibitor, achieves stable plasma concentrations over 24 hours with once-daily dosing. This study evaluated dasotraline in children aged 6–12 years (NCT02428088).

Patients were randomized 1:1:1 to 6 weeks of once-daily, fixed-dose dasotraline 2 or 4 mg/day, or placebo. The primary efficacy endpoint was change from baseline (CFB) at Week 6 in ADHD Rating Scale Version IV – Home Version (ADHD RS-IV HV) total score, using a mixed model for repeated measures (MMRM) in the intent-to-treat (ITT) population. Secondary endpoints included Clinical Global Impression-Severity (CGI-S) score and safety endpoints.

The mean age of 342 randomized patients was 9.1 [SD: 1.9] years; 66.7% were male. Overall, 79% of patients completed the study. In the ITT population (N=336), ADHD RS-IV HV total score improved significantly with dasotraline 4 mg/day vs placebo(least squares [LS] mean [SE] CFB at Week 6: –17.53 [±1.31] vs –11.36 [±1.29], respectively, p<0.001; effect size [ES]: 0.48). Inattentiveness and hyperactivity/impulsivity subscale scores significantly improved with 4 mg/day vs placebo at Week 6 (p=0.001, p=0.003, respectively). Improvement in CGI-S score was statistically significant with dasotraline 4 mg/day vs placebo(LS mean [SE] CFB at Week 6: –1.39 [±0.12] vs –1.04 [±0.12], respectively, p=0.040; ES: 0.29). No significant improvement was observed on the ADHD RS-IV HV total score and the CGI-S score for dasotraline 2 mg/day vs placebo. The most frequent treatment-emergent AEs (≥5% and higher than placebo) were (2 mg/day; 4 mg/day; placebo): insomnia (15.3%; 21.7%; 4.3%, all terms combined), decreased appetite (12.6%; 21.7%; 5.2%), weight loss (5.4%; 8.7%; 0%), irritability (3.6%; 7.0%; 6.0%), nasopharyngitis (0.9%; 5.2%; 0.9%), and nausea (0%; 5.2%; 2.6%).

Compared with placebo, dasotraline 4 mg/day significantly improved ADHD symptoms in children, as assessed by ADHD RS-IV HV total score and inattentiveness and hyperactivity/impulsivity subscale scores. Dasotraline was generally well tolerated; most common AEs were insomnia, decreased appetite, weight loss and irritability.

Study sponsored by Sunovion Pharmaceuticals Inc.