An Assessment of Camel Snus Abuse Liability
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An Assessment of Camel Snus Abuse Liability Prepared for R.J. Reynolds Tobacco Company by: Jack E. Henningfield, PhD Reginald V. Fant, PhD Bethea A. Kleykamp, PhD February 1, 2017 Page 1 of 132 Contents 1 Executive Summary of Abuse Liability of Camel Snus ............................................. 4 2 Background .............................................................................................................. 8 2.1 Defining Abuse Liability ...................................................................................... 8 2.2 Relationships Among Abuse Liability, Product Appeal, and Consumer Perception ................................................................................................................. 13 2.3 Relationship Between Abuse Liability and Modified Risk ................................. 14 3 Assessment of the Abuse Liability of Camel Snus ................................................. 20 3.1 Objectives of this report ................................................................................... 20 3.2 Search Strategy ............................................................................................... 20 3.3 Chemistry ......................................................................................................... 21 3.3.1 Camel Snus overview ................................................................................ 21 3.3.2 Nicotine ...................................................................................................... 22 3.3.3 Nicotine levels in Camel Snus compared to other products in the U.S. ..... 25 3.3.4 Products outside of the U.S. ...................................................................... 31 3.3.5 Other constituents or ingredients that may contribute to abuse liability ..... 32 3.3.6 Other variables that may contribute to abuse liability and product appeal . 38 3.3.7 Lessons learned from flavor modification of nicotine gum and lozenge. .... 39 3.3.8 Camel Snus ............................................................................................... 41 3.3.9 Discussion and Conclusions ...................................................................... 42 3.4 Preclinical Pharmacology ................................................................................. 44 3.4.1 Nicotine and Tobacco (not specific to Camel Snus) .................................. 44 3.4.2 Camel Snus ............................................................................................... 45 3.4.3 Discussion and Conclusions ...................................................................... 45 3.5 Animal Behavioral Pharmacology .................................................................... 45 3.5.1 Nicotine and Tobacco (not specific to Camel Snus) .................................. 45 3.5.2 Camel Snus ............................................................................................... 48 3.5.3 Discussion and Conclusions ...................................................................... 49 3.6 Pharmacokinetics and Pharmacodynamics ..................................................... 49 3.6.1 Nicotine and Tobacco (not specific to Camel Snus) .................................. 49 3.6.2 Camel Snus ............................................................................................... 53 3.6.3 Discussion and Conclusions ...................................................................... 66 3.7 Human Studies of Camel Snus ........................................................................ 67 Page 2 of 132 3.7.1 Self-administration and Topography .......................................................... 68 3.7.2 Subjective Ratings ..................................................................................... 70 3.7.3 Subjective and Physiological Withdrawal................................................... 71 3.7.4 Behavioral Economics ............................................................................... 72 3.7.5 Reducing or Stopping Smoking ................................................................. 74 3.7.6 Reducing or Stopping Smokeless Tobacco Use ........................................ 77 3.7.7 Additional Considerations .......................................................................... 77 3.7.8 Discussion and Conclusions ...................................................................... 78 3.8 Epidemiology .................................................................................................... 80 3.8.1 Tobacco (not specific to Camel Snus) – Federal Survey Data .................. 81 3.8.2 Camel Snus ............................................................................................... 87 3.8.3 Discussion and Conclusions ...................................................................... 89 4 References ............................................................................................................. 91 5 Appendix A: pH, Nicotine, and Free Nicotine in Swedish Match Products ........... 109 6 Appendix B: Overview of nicotine content/delivery across products .................... 110 7 Appendix C: Overview of Camel Snus Styles and Ingredients ............................. 112 8 Appendix D: Summary of Camel Snus Styles ...................................................... 113 9 Appendix E: Overview of Human Studies of Camel Snus .................................... 114 10 Appendix F: Urinary Biomarkers and Camel Snus ............................................... 123 11 Appendix G: Federal Survey Data........................................................................ 125 12 Appendix H: RJRT National Tobacco Behavior Monitor (NTBM) Tobacco Use Patterns Across Products (NTBM) .............................................................................. 131 Page 3 of 132 1 Executive Summary of Abuse Liability of Camel Snus Abuse liability refers to the risk that use of a substance or product will lead to psychological and physiological dependence, along with persistent self-administration and impeded ability to discontinue use of the substance (Food and Drug Administration [FDA], 2010, 2012a). Assessment of the abuse liability of a substance or product is accomplished by a variety of methods that may include in vitro, nonclinical and human participant studies of: • where in the central nervous system (CNS) the substance acts, • to what receptors it binds to determine the pharmacological site(s) of action • direct and indirect effects on neurotransmitter systems associated with abuse potential • animal and human behavioral pharmacology studies including discriminative and reinforcing effects • human abuse potential studies including assessment of liked and positive effects, and its behavioral effects, such as reinforcement and production of pleasure • physical dependence potential studies including assessment of tolerance and withdrawal • patterns of self-administration of the substance, and • epidemiological data. Such lines of evidence are described and relied upon by the FDA Center for Tobacco Products (CTP) for evaluating tobacco products and by the FDA Center for Drug Evaluation and Research (CDER) for evaluating pharmaceutical products (FDA, 2010, 2012a, 2015). The abuse liability of nicotine has been very well characterized, and it is accepted that nicotine has a prominent role in the abuse liability of tobacco products (FDA, 1995; United States Department of Health and Human Services [USDHHS], 1988, 2010, 2014). However, it is also recognized that the formulation of a product that contains nicotine substantially determines its effects and, thus, nicotine delivering products vary widely in their abuse liability – from the minimal abuse liability associated with FDA- approved transdermal nicotine patches to the high abuse liability associated with traditional cigarettes (FDA, 1995; USDHHS, 1988, 2010, 2014). The 2012 Draft Guidance for Modified Risk Tobacco Product (MRTP) Applications mandates that the product proposed for authorization as an MRTP be evaluated for abuse liability. Such an evaluation would determine if use of the proposed product (i.e., Camel Snus in RJRT’s MTRP Application) would contribute to reduced individual harm and public health risk if used in place of other tobacco products (e.g., cigarettes). This is similar in concept to assessing, for example, the relative carcinogenicity, cardiotoxicity, and oral disease risk of the two tobacco products, although available methods for assessment of abuse liability may reasonably be described as less quantitative than are measures of some other biological effects, and as having a subjective component that Page 4 of 132 may differ among individuals. However, there is one important difference – whereas adverse effects (e.g., carcinogenicity, cardiotoxicity, and oral disease risk) should be ideally reduced to the greatest possible extent, some of the effects that contribute to abuse liability must remain sufficient for a putative MRTP to adequately substitute for the reinforcing effects of traditional cigarette smoking that have been well-documented over time (FDA, 1995; USDHHS, 1988, 2010, 2014; also see discussion in Cobb et al., 2010; National Institute on Drug Abuse, 2016). Thus, an abuse liability assessment is relevant for assessing potential risks and benefits associated with Camel Snus being considered a MRTP. This rationale also keeps in mind that the FDA could reject authorization of a product for which the abuse liability was determined to