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NCT Number: NCT03998735

Nornicotine in Smokeless Tobacco as a Precursor for Carcinogen Exposure

Our goal in this study is to investigate the extent of endogenous nitrosation of nornicotine in smokeless tobacco users as a function of nornicotine content in smokeless products. This study will lead to an understanding of the endogenous formation of NNN from nornicotine in humans, and will also investigate the effect of the reduction of nornicotine content in smokeless tobacco on the extent of endogenous NNN formation. The knowledge gained in this study will lead to the development of recommendations for the regulation, or potentially elimination, of nornicotine in smokeless tobacco products in order to minimize exposure to NNN in the users of these products.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

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Key information

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

Masonic Cancer Center

Minneapolis, Minnesota, 55411, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Male or female adult smokeless tobacco users 18-65 years of age, using at least 3 tins of product per week for 6 months;
  • Used the same brand for >80% of their smokeless tobacco use over the course of at least 6 months, and used this brand exclusively for at least two weeks prior to the eligibility screening;
  • Not smoking or using any other nicotine or tobacco product in the past 2 weeks (expired CO < 6 ppm);
  • Participants are in good physical health (no unstable medical condition) and good general oral health as determined by the licensed medical professional;
  • Participants are in stable, good mental health (e.g. not currently, within the past 6 months, experiencing unstable or untreated psychiatric diagnosis, including substance abuse) as determined by the licensed medical professional;
  • Participants who are not taking any medications that affect relevant metabolic enzymes;
  • Women who are not pregnant or nursing or planning to become pregnant;
  • Participants have provided written informed consent to participate in the study.

Exclusion criteria

  • Significant immune system disorders, respiratory diseases, kidney or liver diseases or any other medical disorders that may affect biomarker data as determined by the licensed medical professional;
  • Vital signs out of range as determined by the licensed medical professional (participants failing for vital signs will be allowed to re-screen once):
  • Evident poor oral health (significant gum recession, dental caries, tooth loss) as determined by the general oral health status check;
  • Excessive drinking (e.g., 5 or more drinks daily) or problems with drinking or drugs (e.g., self-report of binge drinking alcohol or treatment for drug or alcohol abuse within last 3 months); to be assessed by PI or licensed medical professional;
  • Regular smoking or tobacco use (e.g., greater than once a week) other than oral smokeless tobacco products;
  • Currently (within the past 2 weeks) using nicotine replacement or other tobacco cessation products (to minimize confounding effects of another product);

Treatment and study plan

Herbal Snuff (Smokeless Tobacco)

Drug

4 levels of [D4]nornicotine in herbal snuff

Primary outcomes

  1. To investigate endogenous formation of NNN in smokeless tobacco users.

    Time frame: 2 Weeks

    Presence of urinary [pyridine-D4]NNN ([D4]NNN)

  2. To investigate endogenous formation of NNN in smokeless tobacco users.

    Time frame: 2 Weeks

    Level of urinary [pyridine-D4]NNN ([D4]NNN) present

Sponsors and collaborators

Lead sponsor

Masonic Cancer Center, University of Minnesota

Other

Collaborators

  • National Institutes of Health (NIH)

Registry information

Important dates

Study start
2021
Primary completion
2025
Study completion
2026
First posted
Jun 26, 2019
Registry last updated
Nov 26, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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