Model-Guided Antipsychotic Dose Reduction in Schizophrenia: A Single-Blind Randomized Controlled Trial

Model-Guided Antipsychotic Dose Reduction in Schizophrenia: A Single-Blind Randomized Controlled Trial - Model-Guided Antipsychotic Dose Reduction in Schizophrenia: A Single-Blind Randomized Controlled Trial

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000014976

Enrollment

Registered

2014-08-28

Start date

2014-09-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Schizophrenia

Interventions

The dose will be reduced to an individually estimated target dose that correspond to 65% dopamine D2 receptor blockade at trough. The dose will be maintained throughout the study period.

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: (1) DSM-IV and DSM5 diagnosis of schizophrenia (2) Having received a stable dose of risperidone or olanzapine for the previous 3 months (3) 18 years-old or older and being capable of providing informed consent

Exclusion criteria

Exclusion criteria: (1) Concomitant use of antipsychotic drugs other than quetiapine at 50 mg or less or its chlorpromazine equivalent at bedtime (2) History of treatment with long-acting risperidone within 6 months (3) Active suicidal ideations or past suicide attempts (4) Presence of severe physical condition, mental retardation, or active substance abuse

Design outcomes

Primary

Measure	Time frame
Rate of successful completers	—

Secondary

Measure	Time frame
Positive and Negative Syndrome Scale	—

Countries

Japan

Contacts

Public ContactHiroyuki Uchida

Minamihanno Hospital Department of Psychiatry

hiroyuki.uchida.hu@gmail.com042-972-7111

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026