A Phase 2a Randomized, Placebo-Controlled Study to Evaluate the Safety and Efficacy of GXV813 in Hospitalized Adults with Schizophrenia

The primary objective is to evaluate the efficacy of GXV813 compared to placebo regarding positive and negative symptoms in adult inpatients experiencing an acute episode of schizophrenia. 5 The secondary objectives include:

• Assessment of overall safety and tolerability.
• Evaluation of the responder rate difference between treatment arms.
• Analysis of the effect on illness severity.
• Determination of pharmacokinetics.

This study involves 100 adult inpatients diagnosed with schizophrenia according to DSM-5 criteria. The participant population includes both males and females between the ages of 18 and 65 years. Inclusion requires an acute exacerbation with an onset of less than two months prior to screening and a Positive and Negative Syndrome Scale total score between 80 and 120. Eligible individuals must require hospitalization for their current symptoms and be capable of providing informed consent. The cohort consists of vulnerable patients who are willing to remain in a clinical setting for the duration of the study.

This Phase 2a, randomized, participant- and investigator blinded, parallel-group, placebo-controlled, multicenter study is designed to evaluate the safety, tolerability, and treatment response of GXV813 in hospitalized adults diagnosed with schizophrenia. The trial methodology involves comparing the efficacy of the investigational product against a placebo regarding positive and negative symptoms during an acute episode. The research protocol includes a screening visit to assess eligibility via DSM-5 criteria and the Positive and Negative Syndrome Scale. Following screening, participants are randomized to receive either the test substance or a placebo. The primary endpoint is the change from baseline in the total scale score at 6 weeks. Secondary assessments include clinical laboratory tests, vital signs, ECG findings, and various psychiatric rating scales. The duration of participant involvement is centered around the treatment period and subsequent follow-up visits, concluding with an end-of-study visit.

The experimental treatment consists of GXV813, administered as a hard capsule. The substance is delivered via an oral route.

The control group receives a placebo in the form of a 0 mg hard gelatin capsule.

The primary efficacy endpoint is the change from baseline in the Positive and Negative Symptom Scale (PANSS) total score at week 6. Secondary efficacy assessments include the participant response, which is defined as either a clinically significant reduction in the PANSS total score of ≥30% or a 1-point difference in the Clinical Global Impression-Severity (CGI-S) scale at week 6. Additional evaluations at week 6 consist of the change from baseline in the PANSS positive subscore, the PANSS negative subscore, and the Marder negative factor score, as well as the change from baseline in the CGI-S scale.

Further secondary parameters involve the assessment of:

• Modified Simpson-Angus Scale (mSAS),
• Barnes Akathisia Rating Scale (BARS),
• Abnormal Involuntary Movement Scale (AIMS),
• Columbia Suicide Severity Rating Scale (C-SSRS),
• Pharmacokinetics (PK) parameters, including the area under the plasma concentration-time curve (AUC) and maximum observed plasma concentration (Cmax).