Tiagabine for Schizophrenia

Age: 18 - 65

Sex: Any

Trial Phase: Phase 3

Sponsor: Beth Israel Deaconess Medical Center

Must be taking: Second-generation antipsychotics

Disqualifiers: Schizoaffective, Seizures, Substance dependence, others

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 6 months

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests tiagabine, a medication, to determine if it can correct brain issues in individuals with early schizophrenia. Participants will receive either tiagabine with their current antipsychotic medications or a placebo. This trial suits those diagnosed with schizophrenia within the last three years and who have taken second-generation antipsychotics for at least three months. As a Phase 3 trial, this study represents the final step before FDA approval, providing participants an opportunity to contribute to a potentially groundbreaking treatment.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it requires participants to be on second-generation antipsychotics for at least 3 months. It seems you may need to continue your current antipsychotic medication.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that tiagabine (Gabitril) is generally safe for people. Previous studies indicate it does not increase the risk of serious mental health issues or severe seizures like status epilepticus. Specifically, individuals taking tiagabine have not experienced more severe mental health problems or major seizures than those not taking it. This trial is testing tiagabine for schizophrenia, and the FDA has already approved tiagabine for treating seizures, indicating its safety is well understood. It is important to consult a doctor to understand what this means for individual circumstances. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for schizophrenia?

Tiagabine is unique because it works differently from standard antipsychotic treatments for schizophrenia. While most treatments focus on dopamine pathways, tiagabine enhances the brain's natural calming system by increasing the availability of GABA, an inhibitory neurotransmitter. This novel mechanism could potentially reduce symptoms with fewer side effects, making it an exciting prospect for patients who don't respond well to traditional antipsychotics. Researchers are optimistic that tiagabine could offer a new avenue for managing schizophrenia, especially for those who struggle with current therapies.

What evidence suggests that tiagabine might be an effective treatment for schizophrenia?

Research has shown that adding tiagabine to antipsychotic medications might aid brain development in young people with early schizophrenia. Early findings suggest tiagabine could affect the brain areas involved in thinking and decision-making. Some participants in this trial will receive tiagabine alongside their antipsychotic regimen, while others will receive a placebo with their antipsychotic medications. Studies have found that tiagabine does not increase the risk of new psychiatric symptoms like psychosis, which involves losing touch with reality. Although tiagabine is already used for other conditions, its potential benefits for schizophrenia remain under study. These early results offer promise for those exploring treatment options for schizophrenia. ^{2 3 5 6 7}

Who Is on the Research Team?

T.-U. Wilson Woo, M.D., Ph.D.

Principal Investigator

Beth Israel Deaconess Medical Center, Harvard Medical School

Are You a Good Fit for This Trial?

This trial is for young adults aged 18-25 who have been diagnosed with schizophrenia within the last three years and are on second-generation antipsychotics. It's not for those with schizoaffective disorder, multiple failed antipsychotic trials, neurological disorders, pregnancy, HIV, suicidal tendencies or substance dependence.

Inclusion Criteria

I was diagnosed with schizophrenia in the last 3 years.

I have been taking second-generation antipsychotics for over 3 months.

Exclusion Criteria

I have a history of seizures or neurological disorders.

Actively suicidal

I am HIV positive.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive tiagabine or placebo in addition to their antipsychotic regimen

6 months

Regular visits for medication administration and monitoring

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Placebo
• Tiagabine

Trial Overview

The study tests if tiagabine can correct brain deficits in early-stage schizophrenia compared to a placebo. Participants will be randomly assigned to receive either tiagabine or an inactive pill without knowing which one they're getting.

How Is the Trial Designed?

Group I: Antipsychotic plus study drug Active Control 1 Intervention

Half of the subjects will receive the study medications in addition to their ongoing antipsychotic regimen.

Group II: Antipsychotics plus placebo Placebo Group 1 Intervention

Half of the subjects will receive placebo in addition to their antipsychotic regimen.

Who Is Running the Clinical Trial?

Beth Israel Deaconess Medical Center

Lead Sponsor

Trials

872

Recruited

12,930,000+

Dartmouth-Hitchcock Medical Center

Collaborator

Trials

548

Recruited

2,545,000+

Citations

1.

clinicaltrials.gov

clinicaltrials.gov/study/NCT00179465

Study Details | NCT00179465 | Treating Schizophrenia by ...

The purpose of this study is to determine whether treatment with tiagabine (Gabitril) during the early course of schizophrenia can fundamentally correct the ...

2.

psychiatryonline.org

psychiatryonline.org/doi/10.1176/pn.40.9.00400029b

GABA Targeted For Study In Schizophrenia

In other words, it looks as if tiagabine “may be effective in modifying the late development of prefrontal circuitry in young patients with recent-onset ...

3.

dash.harvard.edu

dash.harvard.edu/server/api/core/bitstreams/7312037e-bdb5-6bd4-e053-0100007fdf3b/content

https://dash.harvard.edu/server/api/core/bitstream...

... tiagabine or placebo added on to their antipsychotic regimen. Results: Our data suggest that treatment with tiagabine during the early course of the illness ...

4.

pubmed.ncbi.nlm.nih.gov

pubmed.ncbi.nlm.nih.gov/11952769/

Occurrence of psychosis in patients with epilepsy ...

Conclusions: TGB administration appears to carry no significant increased risk of treatment-emergent psychosis. Psychiatric history was not predictive of the ...

5.

accessdata.fda.gov

accessdata.fda.gov/drugsatfda_docs/nda/97/020646ap_gabitril_medrp2.pdf

NDA #20-646 Efficacy - accessdata.fda.gov

Summary: By the sponsor's admission this study did not successfully demonstrate efficacy of tiagabine 36 mg monotherapy in the treatment of Partial seizures.

6.

pubmed.ncbi.nlm.nih.gov

pubmed.ncbi.nlm.nih.gov/11520323/

Long-term safety of tiagabine

TGB does not appear to cause an excess risk of psychosis or increase the incidence of status epilepticus or spike/wave discharges.

7.

withpower.com

withpower.com/trial/phase-3-schizophrenia-10-2003-21fcf

Tiagabine for Schizophrenia · Info for Participants

The purpose of this study is to determine whether treatment with tiagabine (Gabitril) during the early course of schizophrenia can fundamentally correct the ...