Effects of Buspirone Combined with Clozapine

Chuanfu Song

Status and phase: Completed; Early Phase 1

Conditions: Schizophrenia

Treatments: Drug: Low-dose group (buspirone tablets, clozapine); Drug: Control group (clozapine, placebo); Drug: High-dose group (buspirone tablets, clozapine)

Study type: Interventional

Funder types: Other

Identifiers

NCT06906224

Wuhu4thPeopleH001

Details and patient eligibility

About

This study aimed to evaluate the enhancing effects of different doses of buspirone on psychiatric symptoms and cognitive function in patients with schizophrenia. The investigators adopted a prospective, randomised, double-blind, placebo-controlled study design and included 46 patients with schizophrenia being treated at the Fourth People's Hospital of Wuhu. The patients were randomly divided into three groups: the control group, the low-dose group and the high-dose group. The control group received clozapine monotherapy, while the experimental groups received additional buspirone at different doses in addition to clozapine. The Positive and Negative Syndrome Scale (PANSS) and the Chinese version of the Repeatable Battery for the Assessment of Neuropsychological Status were used to evaluate psychiatric symptoms and cognitive function.

Enrollment: 46 patients

Sex: All

Ages: 1 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Aged 18-65 years;
• Meeting the diagnostic criteria for chronic schizophrenia in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV)
• Current remission of psychotic symptoms. The patients had a relatively stable mental state in the past 4 weeks, with a total score of ≤60 points and a score of ≤4 points on the Positive and Negative Syndrome Scale (PANSS)[15], and there were no signs of acute psychotic symptoms. To ensure that patients were included in the chronic phase, only patients who had been diagnosed with schizophrenia for ≥1 year were recruited, thus avoiding confusion with acute phase cases;
• Receiving monotherapy with antipsychotic drugs, such as clozapine.

Exclusion criteria

• Pregnant or lactating women;
• Patients allergic to buspirone;
• Patients previously diagnosed with cognitive impairment, such as dementia or intellectual disability;
• Patients with a history of other brain injuries or diseases, such as stroke, traumatic brain injury, epilepsy or intracranial infection;
• Patients with severe liver or kidney insufficiency;
• Patients with severe physical diseases or other mental illnesses, such as bipolar disorder, major depressive disorder, alcohol or substance dependence;
• Patients with a history of using drugs that affect cognitive function during the study period or those who need to adjust the existing treatment regimen;
• Patients who are unable to cooperate with cognitive function tests or have poor treatment compliance.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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46 participants in 3 patient groups

Control group

Active Comparator group

Description:

Patients received oral clozapine (Jiangsu Pharmaceutical Co., Ltd., Approval No. H32022963) in combination with a placebo. Each dose of the placebo was 1 mg, taken three times a day. Use of placebo: This study employed a double-blind design. Patients in the control group received clozapine monotherapy and took a placebo concurrently. The placebo was identical to buspirone tablets in terms of appearance, shape, colour and packaging to guarantee the double-blind nature of the study. The placebo was custom-made by a third-party pharmaceutical company. Its label only stated 'placebo' and was exactly the same as that of buspirone tablets. This design was intended to eliminate the potential impact of the placebo effect on the study results.

Treatment:

Drug: Control group (clozapine, placebo)

Low-dose group

Active Comparator group

Description:

Patients received oral buspirone tablets (Jiangsu Enhua Pharmaceutical Co., Ltd., Approval No. H19991024) in combination with clozapine. The total daily dose of buspirone was 15 mg, divided into three administrations. The dose remained unchanged throughout the entire study period.

Treatment:

Drug: Low-dose group (buspirone tablets, clozapine)

High-dose group

Experimental group

Description:

Patients received oral buspirone tablets in combination with clozapine. The initial total daily dose of buspirone was 15 mg, divided into three administrations. One week later, the dose was increased to a total daily dose of 30 mg, also divided into three administrations.

Treatment:

Drug: High-dose group (buspirone tablets, clozapine)