Male Reproductive ProblemPhase 1NCT06755346
The Effects of Cannabis on Male Reproductive Functions
A Phase 1 study testing Cannabis plant (THC 20mg), Cannabis (0%/ THC / 0% CBD) and Cannabis plant (THC 40mg) in people with Male Reproductive Problem, run by Kanako Hayashi at 1 site in United States.
Trial summary
The purpose of this study is to understand the direct effects of cannabis on male reproductive functions. The investigators plan to conduct a double-blind, placebo-controlled clinical trial to examine both the chronic and acute effects of cannabis use on male reproductive functions. Read more about this study
- Who is it for?
- Ages 21 to 64 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Male Reproductive Problem
- What is being tested?
- Cannabis plant (THC 20mg), Cannabis (0%/ THC / 0% CBD) and Cannabis plant (THC 40mg)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 0 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Apr 2025to 30 Mar 2027
- Phase
- Phase 1
- Are there results?
- None posted in the registry
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 21 to 64 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Regular cannabis users (21~64 years-old men) who have used cannabis at least once a week for at least once a year or who have never used cannabis.
- Willingness to abstain from using cannabis on the day of the testing session (minimum 5 hours abstinence).
Who cannot join
- Women
- Adult men, 65 or older, and men under the age of 21
- Serious psychiatric conditions (e.g. psychosis, bipolar I and panic disorder)
- Family history of psychosis
- Chronic medical conditions (e.g., heart disease, diabetes)
- History of adverse experiences with cannabis (e.g., anxiety and panic attacks)
Show all 12Show fewer
- Use of other illicit drugs (not cannabis) in the past 2 months
- Heavy alcohol use (>4 drinks, >4 times/week)
- Smoking/nicotine use
- Infrequent cannabis use (less than once a week for only cannabis users)
- BMI over 34
- Current use of corticosteroids and blood thinners
Trial locations and contacts
1 site in 1 country.
United States1 site
Washington State University
Pullman, Washington, 99164
About this study
Official title: The Acute and Chronic Effects of Cannabis on Reproductive Functions in Men
The purpose of this study is to understand the direct effects of cannabis on male reproductive functions. The investigators plan to conduct a double-blind, placebo-controlled clinical trial to examine both the chronic and acute effects of cannabis use on male reproductive functions. Specifically, the investigators will examine the dose-dependent effects of acute cannabis use on male reproductive parameters, including sperm counts, motility, morphology, and testosterone levels, as well as sperm epimutations.
Participants [cannabis users will be randomly assigned to 1) non-vaping, 2) placebo (vaping without cannabis), and 2 doses of cannabis, 3) 20 and 4) 40mg of THC in cannabis flower obtained from the NIDA drug supply], and 5) non-cannabis users (naïve control, no cannabis or placebo exposure).
Participants will provide surveys (cannabis use and sexual functioning and satisfaction etc.), peripheral blood, and semen.
Read the detailed description
The Volcano Vaporizer will be used to expose cannabis or placebo plants.
- Conditions
- Male Reproductive Problem
- Being tested
- Cannabis plant (THC 20mg), Cannabis (0%/ THC / 0% CBD), Cannabis plant (THC 40mg)
- Keywords
- Cannabis, Sperm counts and motility, Testosterone, Sperm epimutation
- Medical subject headings
- Marijuana Abuse
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Cannabis plant (THC 20mg)Drug
Also called marijuana
Cannabis flower - very High THC (>10%) / Low CBD (<1%)
Cannabis (0%/ THC / 0% CBD)Drug
THC (0%) / CBD (0%) - Placebo marijuana
Cannabis plant (THC 40mg)Drug
Also called marijuana
Cannabis flower - very High THC (>10%) / Low CBD (<1%)
| Study group | Role | What they receive |
|---|---|---|
| Cannabis users: non-vaping | No intervention | Cannabis users (n=20) will be assigned to a non-vaping group. |
| Cannabis users: placebo | Placebo comparator | Cannabis users (n=20) will be assigned to a placebo group. Receives: Drug: Cannabis (0%/ THC / 0% CBD) |
| Cannabis users: 20mg THC in cannabis plant | Active comparator | Cannabis users (n=20) will be assigned to a 20mg THC in cannabis group. Receives: Drug: Cannabis plant (THC 20mg) |
| Cannabis users: 40mg THC in cannabis plant | Active comparator | Cannabis users (n=20) will be assigned to a 40mg THC group. Receives: Drug: Cannabis plant (THC 40mg) |
| non-cannabis users | No intervention | Non-cannabis users (n=20) will be assigned to a non-vaping group. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of participants with treatment-related sperm parameters
Sperm counts and motility, as well as DNA fragmentation, will be examined after vaping or no vaping.
Measured: 30 minutes
Number of participants with treatment-related sperm epimutation
Differentially methylated regions in sperm will be analyzed to examine the effects of cannabis exposure.
Measured: 30 minutes
Number of participants with treatment-related plasma testosterone and THC/THC metabolites
Plasma testosterone and THC/THC metabolites will be analyzed to examine the effects of cannabis exposure.
Measured: 4 hours
Secondary outcomes (1)
Number of participants with treatment-related stress reactivity and food intake
After the vaping session and semen collection, participants will complete the Acute Stress Test. Plsama cortisol will be analyzed before and after the Acute Stress Test. During sobering (~4 hours), snacks (e.g., fruit snacks, granola bars, chips, chocolate, soda, juice, and water) will be available for participants. Investigators will monitor participants via the window in the adjacent room to monitor and record the snacks/beverages participants choose to consume.
Measured: 4 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jan 2025
- Study start1 Apr 2025 (estimated)
- Primary completion30 Mar 2027 (estimated)
- Study completion30 Mar 2027 (estimated)
Why it stopped: We terminated the study. Since the FDA did not approve our study, we could not begin it. I have terminated it.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Male Reproductive ProblemStudies 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 1
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 0 participants (actual)
Sponsor and investigators
- Lead sponsor
- Kanako Hayashi
- Sponsor type
- University, hospital or other
- Collaborators
- Washington State University
- Responsible party
- Sponsor-investigator, Kanako Hayashi, Washington State University
- Investigators
- Kanako Hayashi, PhD, Principal investigator, Washington State University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06755346
- Sponsor's protocol ID
- WSU_IRB#20730
- Status last verified
- Jan 2025
- First submitted
- 19 Dec 2024
- Last updated
- 19 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided: This is our first small study to obtain preliminary results. We plan to propose to investigate the effects of acute and chronic cannabis exposure on male reproductive functions in humans, which include single or multiple cannabis vaping exposures and multiple semen collections in the same individual with a larger sample of participants. The data from the large study will be shared.
Study at a glance
From the registry record, last updated by the sponsor on 19 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Acute and Chronic Effects of Cannabis on Reproductive Functions in Men
- ClinicalTrials.gov ID
- NCT06755346
- Acronym / sponsor ID
- WSU_IRB#20730
- Conditions
- Male Reproductive Problem
- Keywords
- Cannabis, Sperm counts and motility, Testosterone, Sperm epimutation
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- WithdrawnReason stopped: We terminated the study. Since the FDA did not approve our study, we could not begin it. I have terminated it.
- Enrolment
- 0 participants (actual)
- Lead sponsor
- Kanako HayashiUniversity, hospital or other
- Collaborators
- Washington State University
- Study start
- 1 Apr 2025 (estimated)
- Primary completion
- 30 Mar 2027 (estimated)
- Study completion
- 30 Mar 2027 (estimated)
- First posted
- 1 Jan 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to understand the direct effects of cannabis on male reproductive functions. The investigators plan to conduct a double-blind, placebo-controlled clinical trial to examine both the chronic and acute effects of cannabis use on male reproductive functions. Specifically, the investigators will examine the dose-dependent effects of acute cannabis use on male reproductive parameters, including sperm counts, motility, morphology, and testosterone levels, as well as sperm epimutations.
Participants [cannabis users will be randomly assigned to 1) non-vaping, 2) placebo (vaping without cannabis), and 2 doses of cannabis, 3) 20 and 4) 40mg of THC in cannabis flower obtained from the NIDA drug supply], and 5) non-cannabis users (naïve control, no cannabis or placebo exposure).
Participants will provide surveys (cannabis use and sexual functioning and satisfaction etc.), peripheral blood, and semen.
Detailed description
The Volcano Vaporizer will be used to expose cannabis or placebo plants.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 5
| Arm | Type | Receives |
|---|---|---|
| Cannabis users: non-vaping | No intervention | –Cannabis users (n=20) will be assigned to a non-vaping group. |
| Cannabis users: placebo | Placebo comparator | Drug: Cannabis (0%/ THC / 0% CBD)Cannabis users (n=20) will be assigned to a placebo group. |
| Cannabis users: 20mg THC in cannabis plant | Active comparator | Drug: Cannabis plant (THC 20mg)Cannabis users (n=20) will be assigned to a 20mg THC in cannabis group. |
| Cannabis users: 40mg THC in cannabis plant | Active comparator | Drug: Cannabis plant (THC 40mg)Cannabis users (n=20) will be assigned to a 40mg THC group. |
| non-cannabis users | No intervention | –Non-cannabis users (n=20) will be assigned to a non-vaping group. |
Who may qualify
- Ages
- 21 to 64 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (2 listed)
- Regular cannabis users (21~64 years-old men) who have used cannabis at least once a week for at least once a year or who have never used cannabis.
- Willingness to abstain from using cannabis on the day of the testing session (minimum 5 hours abstinence).
Key exclusion criteria (12 listed)
- Women
- Adult men, 65 or older, and men under the age of 21
- Serious psychiatric conditions (e.g. psychosis, bipolar I and panic disorder)
- Family history of psychosis
- Chronic medical conditions (e.g., heart disease, diabetes)
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 |
|---|---|---|
| Cannabis plant (THC 20mg)Also: marijuanaCannabis flower - very High THC (>10%) / Low CBD (<1%) | Drug | Cannabis users: 20mg THC in cannabis plant |
| Cannabis (0%/ THC / 0% CBD)THC (0%) / CBD (0%) - Placebo marijuana | Drug | Cannabis users: placebo |
| Cannabis plant (THC 40mg)Also: marijuanaCannabis flower - very High THC (>10%) / Low CBD (<1%) | Drug | Cannabis users: 40mg THC in cannabis plant |
Primary outcome
Number of participants with treatment-related sperm parameters
Time frame: 30 minutes
Sperm counts and motility, as well as DNA fragmentation, will be examined after vaping or no vaping.
Number of participants with treatment-related sperm epimutation
Time frame: 30 minutes
Differentially methylated regions in sperm will be analyzed to examine the effects of cannabis exposure.
Number of participants with treatment-related plasma testosterone and THC/THC metabolites
Time frame: 4 hours
Plasma testosterone and THC/THC metabolites will be analyzed to examine the effects of cannabis exposure.
1 secondary outcome
Number of participants with treatment-related stress reactivity and food intake
Time frame: 4 hours
Results and safety
The study was withdrawn before enrolling participants, so there are no results.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Aug 2026.
- Individual participant dataSharing planned: Undecided. This is our first small study to obtain preliminary results. We plan to propose to investigate the effects of acute and chronic cannabis exposure on male reproductive functions in humans, which include single or multiple cannabis vaping exposures and multiple semen collections in the same individual with a larger sample of participants. The data from the large study will be shared.
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.
Kanako Hayashi, PhD principal investigator
Washington State University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Cannabis plant (THC 20mg), Cannabis (0%/ THC / 0% CBD) and Cannabis plant (THC 40mg) in people with Male Reproductive Problem, run by Kanako Hayashi 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 2 inclusion and 12 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: withdrawn, as of the sponsor's last update on 19 Aug 2026. 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 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study was withdrawn before enrolling participants, so there are no results.
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?
Number of participants with treatment-related sperm parameters (time frame: 30 minutes). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 19 Aug 2026.