A Study Assessing the Efficacy and Safety of HS-10380 in Hospitalized Adults With Acute Schizophrenia

This trial is a Phase 2b, randomized, double-blind, parallel-group, active-controlled and placebo-controlled, multicenter inpatient study, aims to further evaluate the efficacy and safety of HS-10380 in participants with acute schizophrenia, who were randomized (2:2:2:1:2) to receive HS-10380 ( Low Dose), HS-10380 (Medium dose), HS-10380 ( High Dose), Aripiprazole, or placebo, with the primary endpoint as the changes from baseline in PANSS total score on D42.

• HS-10380 Low Dose (Drug): W1：dose titration; W 2-3 dose adjust to optimal level；Week 4-6：stable dose
• HS-10380 Medium dose (Drug): W1: dose titration; W 2-3: dose adjust to optimal level; Week 4-6: stable dose
• HS-10380 High Dose (Drug): W1: dose titration; W 2-3: dose adjust to optimal level; Week 4-6: stable dose
• Aripiprazole (Drug): W1: dose titration; W 2-3: dose adjust to optimal level; Week 4-6: stable dose
• Placebo (Drug): W1: dose titration; W 2-3: dose adjust to optimal level; Week 4-6: stable dose

Primary outcomes

• Change from Baseline in Positive and Negative Syndrome Scale (PANSS) Total Score at Week 6 (Day 42) [Baseline and Week 6]: The PANSS is a medical scale used for measuring symptom severity of participants with schizophrenia. The PANSS rating form contains 7 positive symptom scales, 7 negative system scales, and 16 general psychopathology symptom scales. Participants were rated from 1 to 7 on each symptom scale. The total score is the sum of all scales with a minimum score of 30 and a maximum score of 210. A decrease in PANSS total score correlates with an improvement in schizophrenia symptoms.

Secondary outcomes

• Percentage of Positive and Negative Syndrome Scale (PANSS) Responders (>=40% Change in PANSS Total Score) at Day 42 [Baseline and Week 6]: The PANSS is a medical scale used for measuring symptom severity of participants with schizophrenia. The PANSS rating form contains 7 positive symptom scales, 7 negative system scales, and 16 general psychopathology symptom scales. Participants are rated from 1 to 7 on each symptom scale. The total score is the sum of all scales with a minimum score of 30 and a maximum score of 210. A PANSS responder is defined as a participant with at least a 40% change in PANSS total score compared to baseline at D42.
• Change in Marder 5-factor score of the PANSS scale at Day 42 compared with baseline [Baseline and Week 6]: The Marder 5-factor model is a validated subscale classification of the Positive and Negative Syndrome Scale (PANSS), which was proposed by psychiatrist Stephen R. Marder to refine the dimensional assessment of symptom severity in schizophrenia. It divides the 30 items of the PANSS into five distinct symptom domains, namely: Positive symptoms；Negative symptoms；Disorganization symptoms；Excitement/hostility symptoms；Anxiety/depression symptoms.
• Change in Calgary Depression Scale for Schizophrenia (CDSS) score at Day 42 compared with baseline [Baseline and Week 6]: The Calgary Depression Scale for Schizophrenia (CDSS) is a disease-specific, validated rating scale designed exclusively to assess depressive symptoms in patients with schizophrenia. Unlike general depression scales, it avoids overlap with schizophrenia core symptoms (e.g., anhedonia, avolition) that may mimic depressive manifestations, thus ensuring the accuracy of depression symptom evaluation in this population. The scale consists of 9 items, each rated on a 4-point Likert scale (0 = absent, 1 = mild, 2 = moderate, 3 = severe). The items cover key depressive domains including depressed mood, hopelessness, suicidal ideation, guilt feelings, insomnia, reduced appetite, early morning awakening, psychomotor retardation, and inability to feel pleasure.
• Change from Baseline in Clinical Global Impression-Severity (CGI-S) Score at Day 42 [Baseline and Week 6]: The CGI-S modified asked the clinician 1 question: "Considering your total clinical experience, how mentally ill is the participant at this time?" The clinician's answer rated on the following 7-point scale: 1 = normal, not at all ill; 2 = borderline mentally ill; 3 = mildly ill; 4 = moderately ill; 5 = markedly ill; 6 = severely ill; 7 = among the most extremely ill participants.
• Clinical Global Impression-Improvement (CGI-I) Score at Day 42 [Week 1 and Week 6]: The Clinical Global Impression-Improvement (CGI-I) is a 7-point scale used to assess the patient's improvement relative to baseline status. The scale ranges from 1 to 7, with lower scores indicating greater improvement:1 = Very much improved;2 = Much improved;3 = Minimally improved;4 = No change;5 = Minimally worse;6 = Much worse;7 = Very much worse.

Sex: All, ages: 18 Years to 65 Years

Inclusion Criteria:

* Participant is aged 18-65 years, inclusive, at screening.
* Body mass index must be ≥18.0 and ≤40.0 kg/m² at screening.
* Participant has a primary diagnosis of schizophrenia established by a comprehensive psychiatric evaluation based on the DSM-5 criteria.
* Participant is experiencing an acute exacerbation or relapse of symptoms, with onset less than 2 months before screening.
* Positive and Negative Syndrome Scale total score between 80 and 120, inclusive, at screening or baseline Score of ≥ 4 (moderate or greater) for ≥ 2 of the following Positive Scale (P) items at screening: Item 1 (P1; delusions)\\Item 2 (P2; conceptual disorganization)\\Item 3 (P3; hallucinatory behavior)\\Item 6 (P6; suspiciousness/persecution).

Exclusion Criteria:

* Judged by the investigator as having treatment-resistant schizophrenia.
* Patients with risk of violent or destructive behavior, or suicidal risk.
* History or presence of clinically significant neuropsychiatric, cardiovascular, urinary, digestive, respiratory, musculoskeletal, metabolic/endocrine, hematological, immune, dermatological, and oncological systems disease or any other condition that, in the opinion of the investigator, would jeopardize the safety of the subject or the validity of the study results.
* Received electroconvulsive therapy within 3 months prior to screening, or received systemic transcranial magnetic stimulation (TMS) therapy within 1 month prior to screening.
* Used clozapine or long-acting antipsychotic medications within 6 months prior to screening, or within 5 half-lives of long-acting antipsychotic medications at screening, whichever is longer.
* Previous inadequate response to adequate dose and duration of aripiprazole treatment (≥20 mg/day for at least 6 weeks).
* History of epilepsy (except febrile convulsions) or neuroleptic malignant syndrome.
* Any surgical condition or medical condition that may significantly affect drug absorption, distribution, metabolism, and excretion, or that may pose a risk to trial participants, such as history of gastrointestinal surgery (gastrectomy, gastroenterostomy, bowel resection, etc.), urinary tract obstruction, or dysuria.
* History of severe allergic reactions.
* Female patients who are pregnant, in puerperium, or lactating at screening or baseline.
* History of drug abuse within 1 year prior to screening.
* History of alcohol abuse within 6 months prior to screening.