SPECT Study With SB-773812 In Schizophrenic Patients

A Parallel Study to Investigate Dopaminergic D2 and Serotoninergic 5HT2A Receptor Occupancy at Stable Plasma Concentrations of SB-773812 After Repeated Doses in Schizophrenic Patients. Relationship With Pharmacokinetics and Efficacy Readouts.

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00269035

Enrollment

Registered

2005-12-23

Start date

2005-06-21

Completion date

2007-05-26

Last updated

2017-08-17

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

Conditions

Schizophrenia

Keywords

SB-773812, SPECT, D2 RO, pharmacokinetics, schizophrenic patients, 5HT2A RO

Brief summary

This study is being conducted in 2 groups of schizophrenic patients: in group 1 the relationship between the dopaminergic D2 receptor occupancy (D2 RO ) and serotoninergic 5HT2A receptor occupancy at stable plasma concentration (Cp) of SB-773812 will be investigated using SPECT scan in up to 15 chronic schizophrenic patients in an open- label design. In group 2 up to 80 patients will receive SB-773812 or Risperidone for 6 weeks to obtain at least 10 patients showing clinical improvement with SB-773812. The relationship of D2 RO, measured at steady state after chronic dosing at Cmax (6+/-2 h) and Ctrough (24+/-4 h), and PK at steady state after repeated doses, to efficacy readouts will be investigated. The SB-773812 dose administered will be selected as the highest dose proven to be safe and well tolerated from a previous study.

Interventions

DRUGSB773812

SB-773812 tablets will be available with dose strength of 60 mg

DRUGRisperidone

Risperidone tablets will be available with dose strength of 3 and 6 mg

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Eligibility

Sex/Gender

ALL

Age

18 Years to 55 Years

Healthy volunteers

Inclusion criteria

* schizophrenic patients as diagnosed by DSM IV criteria. * In group 2, subject has schizophrenia or schizophreniform disorder and show moderate disease exacerbation, a PANSS score \> 65 and a score in the PANSS positive scale (PANSS-P) =25. * Women of childbearing potential must agree to acceptable method of birth control.

Exclusion criteria

* Subject shows severe exacerbation, extreme instability, high risk for suicide or serious violent behaviour. * Any clinically or laboratory significant abnormality. * Subjects receiving a radiation dose from other activities of more than 10 mSv over any 3 year period. * Subjects with organic brain disease and history of severe head trauma. * Heart pacemaker, metallic prosthesis or other metallic body implants. * Significant head deformity. * Smokers with associated COPD. * History or presence of clinically significant gastro-intestinal, hepatic or renal disease. * History of cholecystectomy or biliary tract disease. * Positive for HBV, HCV or HIV. * Pregnant or lactating women.

Design outcomes

Primary

Measure	Time frame
To investigate in schizophrenic patients the relationship between D2 RO, 5HT2A RO and stable plasma concentrations of SB-773812 (gr.1) and the relationship of D2 RO and PK over time at steady state to efficacy readouts after 6 w treatment (gr.2)	6 weeks

Secondary

Measure	Time frame
To assess the effect of 6 week treatment of SB-773812 on clinical symptoms as measured by Positive and Negative Symptoms Scale (PANSS), cognitive performance and CGI Severity and Improvement as a function of duration of dosing (group 2).	6 weeks

Countries

Spain

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026