A Study of RG1678(RO4917838) in Patients With Persistent, Predominant Negative Symptoms of Schizophrenia.

A Phase III, Multi center, Randomized, 24 Week, Double blind, Parallel group, Placebo controlled Study to Evaluate Efficacy and Safety of RG1678(RO4917838) in Stable Patients With Persistent, Predominant Negative Symptoms of Schizophrenia Treated With Antipsychotics Followed by a 28 Week, Double blind Treatment Period.

Status

Unknown

Phases

Phase 3

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCT2080221370

Enrollment

630

Registered

2011-01-28

Start date

2011-01-28

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

investigational material(s) Generic name etc : RG1678(RO4917838) INN of investigational material : bitopertin Therapeutic category code : 117 Psychotropic agents Dosage and Administration for Investig

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: -Adult patients, aged 18 years and above -Diagnosis of schizophrenia of paranoid, disorganized, residual, undifferentiated or catatonic subtype -Predominant negative symptoms -With the exception of clozapine, patients are on any of the available marketed atypical or typical antipsychotics (treatment with a maximum of two antipsychotics)

Exclusion criteria

Exclusion criteria: -Evidence that patient has clinically significant, uncontrolled and unstable disorder (e.g. cardiovascular, renal, hepatic disorder) -Body Mass Index (BMI) 40 -Depressive symptoms, defined as a score of 9 or greater on the Calgary Depression Rating Scale for Schizophrenia (CDSS) -A score of 3 or greater on the global Parkinsonism item of the ESRS-A

Design outcomes

Primary

Measure	Time frame
-PANSS negative symptoms factor score -Incidence of adverse events. -Mean change from baseline in the PANSS negative symptom factor score at week 24. -Incidence of adverse events at week 24.	—

Secondary

Measure	Time frame
Personal and Social Performance (PSP) Mean change from baseline in the Personal and Social Performance (PSP) total score at week 24.	—

Outcome results

None listed

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