A Phase 1 interventional study of (S)-Nicotine and (R)- nicotine in Nicotine Dependence and Nicotine Vaping, sponsored by University of California, San Francisco. Recruiting at 1 site in United States. Open to participants aged 21 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-14.
Sponsored by University of California, San Francisco · Phase 1, Interventional, and Basic science
In a crossover study, experienced electronic cigarette users will vape 3 different forms of nicotine: natural (derived from tobacco), synthetic, or a 50:50 mixture of both natural and synthetic. The investigators will compare nicotine metabolism, cardiovascular effects, patterns of self-administration, and participants' feelings of craving/withdrawal and enjoyment.
1,027 studies on the registry are indexed under Tobacco Use Disorder; 128 are open to participants now.
This study's planned enrollment of 18 is below the median of 90 across 892 interventional studies indexed under Tobacco Use Disorder.
Browse Tobacco Use Disorder studies →University of California, San Francisco is the lead sponsor of 2,169 studies on the registry; 372 are open to participants now.
Of its 267 completed or terminated interventional studies of FDA-regulated products, 202 (76%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Medications
Any stimulant medications (example: Adderall) generally given for ADHD treatment.
Women of must be using an acceptable method of
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will spend 8 hours in the hospital research ward where they will vape e-liquid containing 100% (S)-nicotine.
Drug: (S)-Nicotine · Drug: (R)- nicotine · Drug: Racemic nicotine
Participants will spend 8 hours in the hospital research ward where they will vape e-liquid containing 100% (R)-nicotine.
Drug: (S)-Nicotine · Drug: (R)- nicotine · Drug: Racemic nicotine
Participants will spend 8 hours in the hospital research ward where they will vape e-liquid containing 50% (S)-nicotine and 50% (R)-nicotine.
Drug: (S)-Nicotine · Drug: (R)- nicotine · Drug: Racemic nicotine
Participants will spend 8 hours in the hospital research ward and will vape e-liquid containing 100% (S)-nicotine. They will vape following a standardized session, followed by a 4 hour abstinence period. Participants will then vape as they wish (ad libitum) for 90 minutes.
Participants will spend 8 hours in the hospital research ward and will vape e-liquid containing 100% (R)-nicotine. They will vape following a standardized session, followed by a 4 hour abstinence period. Participants will then vape as they wish (ad libitum) for 90 minutes.
Participants will spend 8 hours in the hospital research ward and will vape e-liquid containing 50% (R)-nicotine and 50% (S)-nicotine. They will vape following a standardized session, followed by a 4 hour abstinence period. Participants will then vape as they wish (ad libitum) for 90 minutes.
Also known as: 50:50 mixture of (S)- and (R)-nicotine
Mean Nicotine Exposure Over Time
Plasma nicotine area under the concentrated time curve (AUC) (ng/ml\*h)
Time frame: Up to 7 hours
Mean Amount of Nicotine Consumed Over Time
Nicotine self-administration determined by device weight change before and after use multiplied by the nicotine concentration in the e-liquid
Time frame: 120 minutes
Plan to share: No
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Studies of the drug tested here: Nicotine
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