NCT07462559

Brief Summary

Ketamine is a dissociative anesthetic developed approximately 60 years ago. Both ketamine and its isomer, esketamine, have been used for over 20 years in the treatment of treatment-resistant depression. Other treatment options for this type of depression include combinations of antidepressants, other medications used in depression treatment (such as lithium), psychotherapy, electroconvulsive therapy, and repetitive transcranial magnetic stimulation. The advantage of ketamine and its stereoisomer, esketamine, over other treatment options is their rapidly emerging antidepressant effect, which becomes apparent within the first few days of treatment. Ketamine is primarily metabolized by the cytochrome P450 (CYP) 3A4 enzyme, but also by the CYP2B6 and CYP2C9 enzymes. However, information on the significance of these different enzymes in ketamine metabolism is incomplete. Due to extensive first-pass metabolism, the bioavailability of orally administered ketamine varies significantly and is, on average, only 8-24%. This makes ketamine unsuitable for oral administration. In the treatment of depression, ketamine is administered as a slow intravenous infusion. The concurrent use of medications that inhibit ketamine metabolism can significantly increase the bioavailability of orally administered ketamine. Cobicistat is a potent inhibitor of the CYP3A4 enzyme, which can significantly increase ketamine bioavailability and reduce interindividual variability by inhibiting ketamine's CYP3A4-mediated metabolism. This might enable the oral use of ketamine. Cannabidiol is a cannabinoid that does not have addictive effects, but may have antidepressant and anxiolytic effects. Cannabidiol might reduce the dissociative side effects associated with ketamine treatment. Clinically, cannabidiol appears to moderately inhibit CYP enzymes in the order of potency: CYP2C19 \> CYP2C9 \> CYP3A \> CYP1A2, and based on in vitro data, it also somewhat inhibits the CYP2B6 enzyme, which is involved in ketamine metabolism. However, its effect on ketamine concentrations cannot be assessed based on current knowledge. The purpose of this study is to investigate the potential effects of cannabidiol, cobicistat, and their concurrent administration on the pharmacokinetics of orally administered ketamine. A secondary objective is to study the effect of cannabidiol on ketamine-induced side effects. Study Methodology: This is a four-phase, randomized, open-label, crossover study involving 12 healthy volunteers. On study days, participants will receive a 56 mg oral dose of ketamine in the research facility, alternately with water, cannabidiol, cobicistat, or both cannabidiol and cobicistat. There will be at least a two-week washout period between study days. The pharmacokinetics of ketamine and other study drugs will be investigated by taking blood samples according to a separate schedule for 11 hours after administration on the study day and the following morning. Pharmacokinetic parameters will be calculated from plasma concentrations of ketamine, cobicistat, cannabidiol, and their metabolites. The primary outcome measure is the total area under the curve (AUC0-∞) of ketamine. Additionally, the effects of the drugs on blood pressure, heart rate, and subjective adverse feeling of the study participants will be examined.

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
12

participants targeted

Target at below P25 for phase_1

Timeline
7mo left

Started Mar 2026

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress34%
Mar 2026Dec 2026

Study Start

First participant enrolled

March 4, 2026

Completed
1 day until next milestone

First Submitted

Initial submission to the registry

March 5, 2026

Completed
5 days until next milestone

First Posted

Study publicly available on registry

March 10, 2026

Completed
10 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2026

Last Updated

March 10, 2026

Status Verified

March 1, 2026

Enrollment Period

10 months

First QC Date

March 5, 2026

Last Update Submit

March 5, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • Area under the plasma concentration - time curve (AUC) of ketamine

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

Secondary Outcomes (8)

  • Area under the plasma concentration - time curve (AUC) for kobisistat, cannabidiol and their metabolites

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

  • Area under the plasma concentration - time curve (AUC) for ketamine metabolites

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

  • Peak plasma concentration for ketamine, kobisistat, cannabidiol and their metabolites

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

  • Half-life for ketamine, kobisistat, cannabidiola and their metabolites

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

  • Time to peak plasma concentration for ketamine, kobisistat, cannabidiola and their metabolites

    Prior to and 15, 30, 45, 60, 75, 90 minutes and 2, 3, 4, 5, 7, 9, 11 and 23 hours after administration the drug.

  • +3 more secondary outcomes

Study Arms (4)

Ketamine

ACTIVE COMPARATOR

250 ml water at 8.00 and 9.00 a.m. on the study day. Study drug dose (Ketamine 10 mg/ml oral solution, UK special, 56 mg) p.o. at 9.00 a.m. on the study day.

Drug: Ketamine 10 mg/ml oral solution, UK special

Ketamine and cobisistat

ACTIVE COMPARATOR

250 ml water at 8.00 and 9.00 a.m. on the study day. Study drug dose (Cobisistat Tybost 150 mg) p.o. at 8.00 a.m. on the study day. Study drug dose (Ketamine 10 mg/ml oral solution, UK special, 56 mg) p.o. at 9.00 a.m. on the study day.

Drug: Ketamine 10 mg/ml oral solution, UK specialDrug: Cobisistat Tybost 150 mg

Ketamine and cannabidiol

ACTIVE COMPARATOR

250 ml water at 8.00 and 9.00 a.m. on the study day. Study drug dose (Cannabidiol Epidyolex 100 mg/ml, 700 mg) p.o. at 8.00 a.m. on the study day. Study drug dose (Ketamine 10 mg/ml oral solution, UK special, 56 mg) p.o. at 9.00 a.m. on the study day.

Drug: Ketamine 10 mg/ml oral solution, UK specialDrug: Cannabidiol Epidyolex 100 mg/ml

Ketamine, cannabidiol and cobisistat

ACTIVE COMPARATOR

250 ml water at 8.00 and 9.00 a.m. on the study day. Study drug dose (Cannabidiol Epidyolex 100 mg/ml, 700 mg) and (Cobisistat Tybost 150 mg) p.o. at 8.00 a.m. on the study day. Study drug dose (Ketamine 10 mg/ml oral solution, UK special, 56 mg) p.o. at 9.00 a.m. on the study day.

Drug: Ketamine 10 mg/ml oral solution, UK specialDrug: Cobisistat Tybost 150 mgDrug: Cannabidiol Epidyolex 100 mg/ml

Interventions

1 x 56 mg (5,6 ml) p.o.

KetamineKetamine and cannabidiolKetamine and cobisistatKetamine, cannabidiol and cobisistat

1 x 150 mg p.o.

Ketamine and cobisistatKetamine, cannabidiol and cobisistat

1 x 700 mg (7 ml) p.o.

Ketamine and cannabidiolKetamine, cannabidiol and cobisistat

Eligibility Criteria

Age18 Years - 45 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • written informed consent
  • age 18-45 years
  • healthy
  • no indications of substance abuse
  • acceptable values in laboratory tests: hemoglobin must be at least at the lower limit of the reference range (men 134 g/l, women 117 g/l), liver values at most at the upper limit of the reference range (P -ALAT: women below 35 U/l, men below 50 U/l; P -AFOS: 35 U/l - 105 U/l; P -GT: women less than 40 U/l, men less than 60 U/l; P -Bil: less than 20 umol/l) and in other results (B -PVKT, P -Krea, P -K and P -Na) only minor values that deviate from normal values, which according to the examining physician's assessment are clinically insignificant. Drug screening (U -Huum-PS) and in women the pregnancy test (P-hCG-tot) should be negative.
  • No significant abnormalities in the ECG

You may not qualify if:

  • significant illness
  • mood disorder or suicidality
  • substance abuse
  • systolic blood pressure over 150 mmHg
  • conduction disorder or other significant abnormality in the ECG
  • smoking
  • regular medication, excluding contraceptives that do not contain estrogens
  • pregnancy or its planning or breastfeeding
  • less than 3 months from the previous clinical trial
  • less than 3 months since donating blood
  • significant overweight or underweight
  • difficult to find elbow veins
  • hypersensitivity to investigational drugs or excipients of medicinal products
  • use of natural products (such as St. John's wort).

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Department of Clinical Pharmacology

Helsinki, Finland

Location

MeSH Terms

Interventions

KetamineSolutions

Intervention Hierarchy (Ancestors)

CyclohexanesCycloparaffinsHydrocarbons, AlicyclicHydrocarbons, CyclicHydrocarbonsOrganic ChemicalsPharmaceutical Preparations

Study Officials

  • Janne T Backman, MD, PhD

    Helsinki University Central Hospital

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Janne T Backman, MD, PhD

CONTACT

Laura Tervala

CONTACT

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

March 5, 2026

First Posted

March 10, 2026

Study Start

March 4, 2026

Primary Completion (Estimated)

December 31, 2026

Study Completion (Estimated)

December 31, 2026

Last Updated

March 10, 2026

Record last verified: 2026-03

Data Sharing

IPD Sharing
Will not share

Locations