MemoryPhase 2NCT06074172

The Effect of Cannabidiol in Learning and Memory of Adults

A Phase 2 study testing Cannabidiol (246mg press pill) in people with Memory, run by Colorado State University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

Search all trials

Trial summary

The main objectives of this study were to test if a singular dose of Cannabidiol (1) enhances the learning and memory of healthy human subjects, (2) test if Cannabidiol has negative effects on Retroactive and Proactive Interference during learning, (3) and test if demographic factors will influence CBD's modulation of… Read more about this study

Who is it for?: Ages 18 years and olderHealthy volunteers can take part
Conditions the study is for: Memory
What is being tested?: Cannabidiol (246mg press pill)
Type of treatment: Pill or oral medicine
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 57 participants
Where: 1 siteUnited States
Study dates: 14 Mar 2020to 6 Nov 2020
Phase: Phase 2
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
All sexes
Healthy volunteers accepted
Adult, Older adult

Who may be able to join

Were 18 years of age or older

Who cannot join

Were pregnant or breast-feeding
Had been diagnosed with mental illness
Didn't speak English fluently
Had severe hearing problems
Had recreational or opioid drug contaminants in their urine
Were involved in criminal activity

Trial locations and contacts

1 site in 1 country.

United States1 site

Colorado State University Pueblo
Pueblo, Colorado, 81001

Other trials in United States

About this study

Read the detailed description

Using a randomized, double-blind, placebo-controlled two-arm case-crossover trial, this study investigates the effect of 246 milligrams (mg) of Cannabidiol (CBD) on the learning and memory scores of human subjects, as well as the effect of Cannabidiol on Proactive and Retroactive Interference. This study also investigated the influence of demographic factors on CBD's modulation of human learning and memory.

This study was conducted at Colorado State University-Pueblo (CSU Pueblo) with volunteers recruited from CSU Pueblo and the local Pueblo community. Fifty-seven subjects were randomized in a double-blind manner to receive either CBD or placebo before completing two versions of learning and memory assessments. Each version of the learning and memory assessment included the Montreal Cognitive Assessment (MOCA), the Rey Auditory Verbal Learning Task-Revised (RAVLT-R), and the Logical Memory Subject of the Weschler Memory Scale. Several components of the RAVLT-R were evaluated including the Sum of Trials (Trials I-V) score, Proactive Interference Ratio (PI Ratio), and Retroactive Interference (RI Ratio).

Conditions: Memory
Being tested: Cannabidiol (246mg press pill), Placebo (246mg press pill)

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Cannabidiol (246mg press pill)Drug
Cannabidiol press pills provided by Steve Goods CBD (Longmont, Colorado). CBD pills were tested by the chemistry lab at CSU Pueblo and by Botanacor in Denver, CO. Both laboratories determined CBD pills to be 99.98% pure with no THC, heavy metals, bacteria, and pesticides detected.
Placebo (246mg press pill)Drug
Placebo press pills were provided by Steve Goods CBD (Longmont, Colorado). Placebo pills were tested by the chemistry lab at CSU Pueblo and by Botanacar in Denver, CO. Both laboratories determined placebo pills to be pure with no heavy metals, bacteria, and pesticides detected.

Study groups in NCT06074172
Study group	Role	What they receive
Placebo, Then Cannabidiol	Placebo comparator	Participants first received a Placebo 246 mg press pill during visit 1. After a washout period of 1 week, subjects received a Cannabidiol press pill during visit 2. Receives: Drug: Placebo (246mg press pill)
Cannabidiol, Then Placebo	Active comparator	Participants first received a Cannabidiol 246 mg press pill during visit 1. After a washout period of 1 week, subjects received a Placebo press pill during visit 2. Receives: Drug: Cannabidiol (246mg press pill)

What is being measured

The primary outcome is the main question the study is designed to answer.

Sum of Trials (I-V)
Sum of Trials = Trial A1 + Trial A2 + Trial A3 + Trial A4 + Trial A5;
Trial A1/A2/A3/A4/A5 are in reference to each trial in which list A is recalled during memory encoding. The score range for Sum of Trials is 0 to 75. A higher score is indicative of greater performance on the memory test and a lower score is indicative of lower performance on the memory test.
Participants were instructed to listen to a list of 15 words (List A) read to them. Subjects were asked recall List A during five different trials (A1, A2, A3, A4, A5), with the words repeated to them after each trial. Participants were scored for the number of correctly repeated words for each trial.
Measured: Each trial is 45 seconds for encoding and recall
Proactive Interference Ratio (PI Ratio)
PI Ratio = Trial B1/A1. Proactive interference is the tendency for previously learned information to affect to hinder learning of new information. A higher proactive interference ratio indicates protective effects on memory i.e. protection from interference during learning. A lower proactive interference is indicative of negative effects on memory caused from interference. Trial A1 is in reference to list A recall during the first trial. Trial B1 is in reference to list B recall. Highest score for each trial is 15 with a point awarded for each correctly recalled word from List A (15 words) and List B (15 words).
Measured: Each trial is 45 seconds for encoding and recall
Retroactive Interference Ratio (RI Ratio)
RI Ratio = Trial A6/A5. Retroactive interference is the tendency for newly learned information to hinder the memory of previously learned information. A higher retroactive interference ratio indicates protection from interference during learning. A lower retroactive interference ratio is indicative of negative effects on memory caused from interference. Trial A6 is referring to delayed recall of list A; Trial A5 is referring to the fifth trial of list A recall. Highest score for each trial is 15 with a point awarded for each word correctly recalled from List A (15 words).
Measured: Each trial is 45 seconds for encoding and recall
Total Prose Recall
Total Prose Recall = Immediate Recall + Delayed Recall; Recall of a prose story was done immediately then after a delay; Highest score for prose recall test is 25 with a point awarded for each item correctly recalled in the story (25 total items). A higher recall score is indicative of better memory.
Measured: Each recall takes about 5 min for encoding and recall
Montreal Cognitive Assessment Score
Assessment of basal cognitive function; The range for Montreal Cognitive Assessment (MOCA) scores is 0 to 30. A higher recall score is indicative of better performance on the memory test. A lower recall score is indicative of worse performance on the memory test.
Measured: 10 minutes total for encoding and recall

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

14 Mar 20206 Nov 2020

First posted10 Oct 2023
Study start14 Mar 2020
Primary completion6 Nov 2020
Study completion6 Nov 2020

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (1)Papers the sponsor has linked to this study.
Other trials for MemoryStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Crossover
Model description: Two-arm Case-Crossover
Masking: Triple blind
Who is masked: Participant, Care provider, Outcomes assessor
Enrolment: 57 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT06074172
Sponsor's protocol ID: MD012420BM
Status last verified: Mar 2025
First submitted: 26 Sep 2023
Last updated: 24 Mar 2025
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: Yes: Individual (de-identified) participant data is to be made available to other researchers.

Publications

Gebregzi HH, Zeiger JS, Smith JP, Stuyt L, Cullen L, Carsella J, Rogers DC, Lafebre J, Knalfec J, Vargas A, Diawara MM. Oral cannabidiol did not impair learning and memory in healthy adults. J Cannabis Res. 2025 Jan 23;7(1):5. doi: 10.1186/s42238-025-00262-2.
PubMed 39849639

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

Not yet recruitingPhase 3
Women Who Are Victims of Violence: Treatment of PTSD Through Reactivation of Traumatic Memories Using Propranolol
Post-Traumatic Stress Disorder, PTSD
RecruitingPhase 1
Lm-LLO-TT and Gemcitabine in Unresectable Pancreatic Ductal Adenocarcinoma
Pancreas Cancer, Duct Cell Adenocarcinoma, Pancreatic Cancer
RecruitingObservational study
Studies of Blood Flow to the Brain During Thought
Healthy Volunteer
Not yet recruitingObservational study
Prospective Research on Identification of Dementia in Early Stages (P.R.I.D.E)
Mild Cognitive Impairment, Memory Disorders
Active, not recruitingObservational study
A Study of Attention and Memory Processes in Breast Cancer Survivors
Breast Cancer Survivors

All Memory trials

Study at a glance

From the registry record, last updated by the sponsor on 24 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: The Effect of Cannabidiol in Learning and Memory of Adults
ClinicalTrials.gov ID: NCT06074172
Acronym / sponsor ID: MD012420BM
Conditions: Memory
Phase: Phase 2
Study type: Interventional
Recruitment status: Completed
Enrolment: 57 participants (actual)
Lead sponsor: Colorado State UniversityUniversity, hospital or other
Collaborators: Institute of Cannabis Research
Study start: 14 Mar 2020 (actual)
Primary completion: 6 Nov 2020 (actual)
Study completion: 6 Nov 2020 (actual)
First posted: 10 Oct 2023 (actual)
Results: Posted 24 Mar 2025

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Crossover
Masking: Triple blind (participant, care provider, outcomes assessor)
Number of arms: 2
Model description: Two-arm Case-Crossover

Arm	Type	Receives
Placebo, Then Cannabidiol	Placebo comparator	Drug: Placebo (246mg press pill)Participants first received a Placebo 246 mg press pill during visit 1. After a washout period of 1 week, subjects received a Cannabidiol press pill during visit 2.
Cannabidiol, Then Placebo	Active comparator	Drug: Cannabidiol (246mg press pill)Participants first received a Cannabidiol 246 mg press pill during visit 1. After a washout period of 1 week, subjects received a Placebo press pill during visit 2.

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Accepted
Age groups: Adult, Older adult

Key inclusion criteria (1 listed)

Were 18 years of age or older

Key exclusion criteria (6 listed)

Were pregnant or breast-feeding
Had been diagnosed with mental illness
Didn't speak English fluently
Had severe hearing problems
Had recreational or opioid drug contaminants in their urine

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Cannabidiol (246mg press pill)Cannabidiol press pills provided by Steve Goods CBD (Longmont, Colorado). CBD pills were tested by the chemistry lab at CSU Pueblo and by Botanacor in Denver, CO. Both laboratories determined CBD pills to be 99.98% pure with no THC, heavy metals, bacteria, and pesticides detected.	Drug	Cannabidiol, Then Placebo
Placebo (246mg press pill)Placebo press pills were provided by Steve Goods CBD (Longmont, Colorado). Placebo pills were tested by the chemistry lab at CSU Pueblo and by Botanacar in Denver, CO. Both laboratories determined placebo pills to be pure with no heavy metals, bacteria, and pesticides detected.	Drug	Placebo, Then Cannabidiol

Primary outcome

Sum of Trials (I-V)
Time frame: Each trial is 45 seconds for encoding and recall
Sum of Trials = Trial A1 + Trial A2 + Trial A3 + Trial A4 + Trial A5; Trial A1/A2/A3/A4/A5 are in reference to each trial in which list A is recalled during memory encoding. The score range for Sum of Trials is 0 to 75. A higher score is indicative of greater performance on the memory test and a lower score is indicative of lower performance on the memory test. Participants were instructed to listen to a list of 15 words (List A) read to them. Subjects were asked recall List A during five different trials (A1, A2, A3, A4, A5), with the words repeated to them after each trial. Participants were scored for the number of correctly repeated words for each trial.
Proactive Interference Ratio (PI Ratio)
Time frame: Each trial is 45 seconds for encoding and recall
PI Ratio = Trial B1/A1. Proactive interference is the tendency for previously learned information to affect to hinder learning of new information. A higher proactive interference ratio indicates protective effects on memory i.e. protection from interference during learning. A lower proactive interference is indicative of negative effects on memory caused from interference. Trial A1 is in reference to list A recall during the first trial. Trial B1 is in reference to list B recall. Highest score for each trial is 15 with a point awarded for each correctly recalled word from List A (15 words) and List B (15 words).
Retroactive Interference Ratio (RI Ratio)
Time frame: Each trial is 45 seconds for encoding and recall
RI Ratio = Trial A6/A5. Retroactive interference is the tendency for newly learned information to hinder the memory of previously learned information. A higher retroactive interference ratio indicates protection from interference during learning. A lower retroactive interference ratio is indicative of negative effects on memory caused from interference. Trial A6 is referring to delayed recall of list A; Trial A5 is referring to the fifth trial of list A recall. Highest score for each trial is 15 with a point awarded for each word correctly recalled from List A (15 words).
Total Prose Recall
Time frame: Each recall takes about 5 min for encoding and recall
Total Prose Recall = Immediate Recall + Delayed Recall; Recall of a prose story was done immediately then after a delay; Highest score for prose recall test is 25 with a point awarded for each item correctly recalled in the story (25 total items). A higher recall score is indicative of better memory.
Montreal Cognitive Assessment Score
Time frame: 10 minutes total for encoding and recall
Assessment of basal cognitive function; The range for Montreal Cognitive Assessment (MOCA) scores is 0 to 30. A higher recall score is indicative of better performance on the memory test. A lower recall score is indicative of worse performance on the memory test.

Results and safety

Results posted to the registry on 24 Mar 2025, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Placebo (Visit 1 Drug Administration)	27	21
Cannabidiol (Visit 1 Drug Administration)	30	23

Primary outcome: Sum of Trials (I-V)

Time frame: Each trial is 45 seconds for encoding and recall. Mean (Standard Error). Unit: score on a scale

Measure	Placebo (Administered During Visits 1 or 2) n = 35	Cannabidiol (Administered During Visits 1 or 2) n = 35
Value	49.09 (1.85)	47.17 (1.85)

Population analysed: The data reported is for 35 adult healthy human subjects who came in for visits 1 and 2 and were randomized to a treatment group (CBD or placebo). Since the 35 subjects came in twice, each of them received both interventions (CBD and placebo).

Primary outcome: Proactive Interference Ratio (PI Ratio)

Time frame: Each trial is 45 seconds for encoding and recall. Mean (Standard Error). Unit: ratio

Measure	Placebo (Visit 1 Drug Administration) n = 35	Cannabidiol (Visit 1 Drug Administration) n = 35
Value	1.04 (0.08)	1.21 (0.08)

Placebo (Visit 1 Drug Administration) vs Cannabidiol (Visit 1 Drug Administration): p = 0.008, Linear Mixed Model

Population analysed: Adult healthy human subjects

Primary outcome: Retroactive Interference Ratio (RI Ratio)

Time frame: Each trial is 45 seconds for encoding and recall. Mean (Standard Error). Unit: ratio

Measure	Placebo (Visit 1 Drug Administration) n = 35	Cannabidiol (Visit 1 Drug Administration) n = 35
Value	0.87 (0.03)	0.83 (0.03)

Population analysed: Adult healthy human subjects

Primary outcome: Total Prose Recall

Time frame: Each recall takes about 5 min for encoding and recall. Mean (Standard Error). Unit: Score on a scale

Measure	Placebo (Visit 1 Drug Administration) n = 35	Cannabidiol (Visit 1 Drug Administration) n = 35
Value	27.49 (1.46)	25.49 (1.46)

Population analysed: Adult healthy human subjects

Adverse events

Time frame: Adverse event data were collected as subjects completed exit surveys at the end of visit 2. Completion of the exit survey took about 15-20 minutes. Assessment administrators also followed up with study participants up until the completion of the study to confirm whether any adverse events occurred or resolved. Study participants confirmed that all adverse events were resolved. Adverse event data was collected at the end of visit 2.. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Placebo (Administered During Visits 1 or 2)	0 of 35 (0%)	1 of 35 (2.9%)	0 of 35
Cannabidiol (Administered During Visits 1 or 2)	0 of 35 (0%)	4 of 35 (11.4%)	0 of 35

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 24 Mar 2025.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Derived from this study: PubMed 39849639Gebregzi HH, Zeiger JS, Smith JP, Stuyt L, Cullen L, Carsella J, Rogers DC, Lafebre J, Knalfec J, Vargas A, Diawara MM. Oral cannabidiol did not impair learning and memory in healthy adults. J Cannabis Res. 2025 Jan 23;7(1):5. doi: 10.1186/s42238-025-00262-2.
Individual participant dataSharing planned: Yes. Individual (de-identified) participant data is to be made available to other researchers.

Related trials for Memory

Not yet recruitingPhase 3
Women Who Are Victims of Violence: Treatment of PTSD Through Reactivation of Traumatic Memories Using Propranolol
Post-Traumatic Stress Disorder, PTSD
RecruitingPhase 1
Lm-LLO-TT and Gemcitabine in Unresectable Pancreatic Ductal Adenocarcinoma
Pancreas Cancer, Duct Cell Adenocarcinoma, Pancreatic Cancer
RecruitingObservational study
Studies of Blood Flow to the Brain During Thought
Healthy Volunteer
Not yet recruitingObservational study
Prospective Research on Identification of Dementia in Early Stages (P.R.I.D.E)
Mild Cognitive Impairment, Memory Disorders
Active, not recruitingObservational study
A Study of Attention and Memory Processes in Breast Cancer Survivors
Breast Cancer Survivors

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Moussa M Diawara, PhD principal investigator

Colorado State University-Pueblo

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 2 study testing Cannabidiol (246mg press pill) in people with Memory, run by Colorado State University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 24 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 24 Mar 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Sum of Trials (I-V) (time frame: Each trial is 45 seconds for encoding and recall). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06074172, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Mar 2025.