THC for Psychosis Risk

Age: 18 - 65

Sex: Any

Trial Phase: Phase < 1

Sponsor: Yale University

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

Duration: 1 day

21 Participants Needed

Trial Summary

What is the purpose of this trial?

The overall purpose of this study is to determine whether a family history of psychosis is associated with an altered cannabinoid system. This will be tested by studying individuals with and without a family history of psychosis and comparing their responses to delta 9-tetrahydrocannabinol (THC), a probe of the cannabinoid system. We hypothesize, that compared to controls with no family history of psychoses, individuals with a family history of psychoses will have an altered response to THC.

Will I have to stop taking my current medications?

The trial requires that participants have not been treated with psychotropic medications for major psychiatric or neurological illness for at least 6 months. If you are currently on such medications, you may not be eligible to participate.

Is low dose THC safe for humans?

Research shows that THC, the active component in cannabis, can cause temporary psychosis-like effects in some people, especially at higher doses or with frequent use. While not everyone will experience these effects, those with a history of mental health issues or who start using cannabis at a young age may be at higher risk. More research is needed to fully understand the safety of low dose THC, particularly in vulnerable groups. ^{1 2 3 4 5}

How does the drug THC for Psychosis Risk differ from other treatments for psychosis?

This treatment is unique because it explores the effects of low and very low doses of THC, the main psychoactive component of cannabis, on psychosis risk, which is different from traditional treatments that do not typically involve THC. The study aims to understand if low doses of THC can be used safely without increasing psychosis risk, unlike high-potency cannabis which is known to increase such risks. ^{6 7 8 9 10}

Research Team

Mohini Ranganathan, MD

Principal Investigator

Yale University

Eligibility Criteria

This trial is for people who have tried cannabis at least once and are medically and mentally healthy. They must also have a relative with a confirmed psychotic disorder. It's not specified who can't join, but typically those with health issues that could interfere would be excluded.

Inclusion Criteria

Exposure to cannabis at least once in their lifetime

Medically and psychiatrically healthy based on screening

I have a family member with a confirmed psychotic disorder.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive placebo, very low dose THC, and low dose THC interventions to study the cannabinoid system

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

1-2 weeks

Treatment Details

Interventions

• Low Dose THC
• Placebo
• Very Low Dose THC

Trial Overview The study aims to see if having a family history of psychosis affects how the body responds to THC, an active component of cannabis. Participants will receive either very low dose THC, low dose THC, or a placebo without knowing which one they're getting.

Participant Groups

Group I: No Family History of Psychosis (FHN) Experimental Treatment 3 Interventions

Individuals recruited with no history of psychosis in the family. They will receive the placebo, very low dose THC, and low dose THC interventions.

Group II: Family History of Psychosis (FHP) Experimental Treatment 3 Interventions

Individuals with a family member with a confirmed diagnosis of psychosis. They will receive the placebo, very low dose THC, and low dose THC interventions.

Who Is Running the Clinical Trial?

Yale University

Lead Sponsor

Trials

1,963

Recruited

3,046,000+

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Cannabis and Psychosis Through the Lens of DSM-5. [2020]

2. England pubmed.ncbi.nlm.nih.gov

Risk-thresholds for the association between frequency of cannabis use and the development of psychosis: a systematic review and meta-analysis. [2023]

3. Switzerland pubmed.ncbi.nlm.nih.gov

Impact of Cannabis Use on the Development of Psychotic Disorders. [2020]

4. England pubmed.ncbi.nlm.nih.gov

Cannabinoids and psychosis. [2022]

5. England pubmed.ncbi.nlm.nih.gov

Psychosis-Relevant Effects of Intravenous Delta-9-Tetrahydrocannabinol: A Mega Analysis of Individual Participant-Data from Human Laboratory Studies. [2021]

6. Germany pubmed.ncbi.nlm.nih.gov

[Effects of (--)delta-9-trans-tetrahydrocannabinol (delta-9-THC) on tests of psychoticism. A study of Eysenck's drug postulate on the effects of hallucinogens in relation to psychoticism (author's transl)]. [2020]

7. United Arab Emirates pubmed.ncbi.nlm.nih.gov

Cannabinoids and Psychosis. [2018]

8. Switzerland pubmed.ncbi.nlm.nih.gov

Unraveling the Intoxicating and Therapeutic Effects of Cannabis Ingredients on Psychosis and Cognition. [2021]

9. United States pubmed.ncbi.nlm.nih.gov

Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment. [2022]

10. Australia pubmed.ncbi.nlm.nih.gov

Preventive interventions targeting cannabis use and related harms in people with psychosis: A systematic review. [2022]