Combining two treatments for schizophrenia

Dual Modulation of Sigma-1 and NMDA Receptors in the Treatment of Schizophrenia

Phase 2 Interventional China Medical University Hospital · NCT06574360

This study is testing if a new combination of two treatments can help people with schizophrenia who haven't responded well to other medications.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment90 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorChina Medical University Hospital Academic / other
Locations1 site (Taichung)
Trial IDNCT06574360 on ClinicalTrials.gov

What this trial studies

This study investigates the effectiveness of a combined treatment approach using a sigma-1 receptor agonist and an NMDA receptor enhancer for patients with treatment-resistant schizophrenia. Participants will be randomly assigned to receive either the combination treatment or a placebo while maintaining their current antipsychotic medications. The study will assess clinical performance and side effects over a 12-week period, with cognitive functions evaluated at the beginning and end of the treatment. The goal is to determine if the combination therapy offers greater benefits than the sigma-1 receptor agonist alone.

Who should consider this trial

Good fit: Ideal candidates are individuals diagnosed with schizophrenia who have not responded adequately to at least two different antipsychotic medications.

Not a fit: Patients with intellectual disabilities or substance use disorders may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could provide a new treatment option for patients with treatment-resistant schizophrenia.

How similar studies have performed: Previous studies have shown some success with NMDA receptor enhancers in schizophrenia, but this specific combination approach is novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Have a DSM-5 (American Psychiatric Association) diagnosis of schizophrenia
* Are resistant to adequate treatments of at least two antipsychotics (excluding clozapine)
* Remain symptomatic but without clinically significant fluctuation, while their antipsychotic doses are unchanged for at least 3 months and will be maintained during the period of the 8-week trial
* PANSS total score \>70
* Hamilton Depression Rating Scale-17 items (HAMD) \<7
* Are physically healthy and laboratory assessments (including blood routine, biochemical tests) are clinically insignificant.
* Have sufficient education to communicate effectively and are capable of completing the assessments of the study.
* Agree to participate in the study and provide informed consent

Exclusion Criteria:

* DSM-5 diagnosis of intellectual disability or substance (including alcohol) use disorder
* History of epilepsy, head trauma, central nervous system diseases or mental disorders other than schizophrenia (including major depressive disorder, bipolar disorders, persistent depressive disorder, obsessive-compulsive disorder)
* Pregnancy or lactation
* Inability to follow protocol

Where this trial is running

Taichung

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SchizophreniaNMDAsigma-1 receptor
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.