Impact of THC on Cigarette Smoking Behavior

Effect of Cannabinoids on Tobacco Product Demand and Pharmacodynamics: Cigarette Use

Phase 1 Interventional Johns Hopkins University · NCT06609083

This study is testing how different amounts of THC affect smoking habits and cravings in healthy adults who smoke cigarettes and use cannabis.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment100 (estimated)
Ages21 Years and up
SexAll
SponsorJohns Hopkins University Academic / other
Locations1 site (Baltimore, Maryland)
Trial IDNCT06609083 on ClinicalTrials.gov

What this trial studies

This study investigates how different doses of tetrahydrocannabinol (THC) affect the motivational, subjective, and physiological responses to cigarette smoking. Using a double-blind, placebo-controlled, within-subjects crossover design, participants will receive varying doses of THC or a placebo while their cigarette use behaviors are monitored. The study aims to assess factors such as tobacco craving, heart rate, blood pressure, and cognitive performance in healthy adults who smoke cigarettes and use cannabis. Participants will be randomized to receive either smoked or vaporized THC to evaluate the effects of different administration routes.

Who should consider this trial

Good fit: Ideal candidates are healthy adults aged 21 or older who smoke cigarettes daily and use cannabis at least once a week.

Not a fit: Patients who intend to quit or reduce their cannabis or tobacco use within the next 30 days may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide insights into how THC influences cigarette smoking behavior, potentially aiding in smoking cessation strategies.

How similar studies have performed: While the effects of THC on smoking behavior have been explored, this specific approach using a controlled laboratory setting and varying doses is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Healthy non-treatment seeking adults aged 21 or older
2. Report daily use of combustible tobacco cigarettes
3. Biological confirmation of cigarette use: have an expired carbon monoxide (CO) level of more than 5 ppm and a positive urine cotinine test at screening
4. Report current use of cannabis (at least 1 occasion per week)
5. Have experience with the inhalation route of administration for cannabis
6. Biological confirmation of cannabis use: have a positive urinary THC drug test at screening.
7. For women of children bearing potential and men with female partners of child-bearing potential, must be willing to use an effective form of contraception during the study.

Exclusion Criteria:

1. Report current intention to reduce or quit cannabis or tobacco use within the next 30 days
2. Meet Diagnostic and Statistical Manual (DSM-5) criteria for a substance use disorder other than alcohol, cannabis, or nicotine
3. Test positive for illicit drugs other than cannabis and tobacco
4. Positive breath alcohol test at study admission
5. Have a current physical or mental illness judged by the study team to negatively impact participant safety or scientific integrity
6. Have a lifetime history of suicidal behavior (i.e. past suicide attempt), or current suicidal behavior or ideation as assessed by the Columbia Suicide Severity Rating Scale (C-SSRS)
7. Are currently pregnant, planning to become pregnant in the next three months or are currently breastfeeding
8. Have a history of clinically significant cardiac arrhythmias or vasospastic disease (e.g., Prinzmetal's angina)
9. Are currently enrolled in another clinical trial or have received any drug as part of a research study within 30 days of study participation.

Where this trial is running

Baltimore, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Cannabis UseTobacco UseCigarette SmokingcannabiscigarettemarijuanaTHCtobacco
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.