Smoking topography and harm exposure in a new PREP

描述（由申请人提供）：大约25%的美国成年人目前是吸烟者，尽管许多人试图戒烟，但大多数人都失败了。作为替代，一些吸烟者使用潜在减少暴露产品（prep）。然而，以前的减害产品，如淡烟，已被证明是一场公共卫生灾难。致癌物暴露研究和流行病学数据表明，代偿性吸烟行为会使轻烟和普通香烟一样有害。因此，重要的是要了解人们如何使用prep，并评估这与他们的危害暴露之间的关系。Quest(r)香烟是一种新型PREP，它使用转基因烟草，通过销售尼古丁含量逐渐降低的香烟（0.6毫克、0.3毫克和0.05毫克），提供一种“逐步实现无尼古丁的方法”。本研究的主要目的是调查香烟尼古丁水平逐渐降低对吸烟地形和危害暴露措施的影响。该研究将是一个主题内的开放标签设计，210名吸烟者目前对戒烟不感兴趣。参与者将被随机分配到三种情况中的一种：1)继续抽自己品牌的烟（对照组）；2)按降压顺序抽Quest(r)香烟，尼古丁水平从0.6 mg逐渐降低到0.3 mg，再到0.05 mg （Quest(r)降压）；或3)以非降压随机顺序抽Quest(r)支香烟，在受试者之间平衡（Quest(r)非降压）。该研究将包括四个阶段，首先是所有参与者为期5天的自有品牌吸烟阶段，然后是三种吸烟条件之一。对于那些吸食Quest(r)香烟的人来说，香烟中的尼古丁水平每10天就会发生变化，要么是逐步下降，要么是随机变化。主要的行为结果是吸烟地形；特别是总吸气量和平均吸气量，这将在每次会议上进行评估。评估烟雾暴露的一氧化碳和尿液生物标志物也将被评估。在基线，参与者将观看Quest(r)广告并完成产品期望调查，以确定对Quest(r)香烟的信念对随后吸烟行为的影响。这项研究有几个重要的公共卫生意义。它将决定如何实际使用一种新的PREP。它还将确定产品使用与危害暴露之间的关系。最后，它将确定那些最容易受到吸烟地形变化的影响，这些变化可能会增加危害暴露。

DESCRIPTION (provided by applicant): Approximately 25% of the adult US population are current smokers, and although many try to quit, most fail. As an alternative, some smokers use potentially reduced exposure products (PREPs). However, prior harm reduction products, such as light cigarettes, have proven to be a public health disaster. Carcinogen exposure studies and epidemiologic data show that compensatory smoking behavior can make light cigarettes as harmful as regular cigarettes. Therefore, it is important to understand how people use PREPs and to assess how this relates to their harm exposure. Quest(r) cigarettes are a new PREP that uses genetically modified tobacco to provide a "step-down approach to becoming nicotine-free" by marketing cigarettes with progressively lower levels of nicotine: 0.6 mg, 0.3 mg and 0.05 mg. The primary aim of the study is to investigate the effect of progressive decreases in cigarette nicotine level on smoking topography and harm exposure measures. The study will be a within-subject, open-label design of 210 smokers not currently interested in quitting. Participants will be randomized to one of three conditions: 1) continue to smoke their own brand (control); 2) smoke Quest(r) cigarettes in the step-down order, progressively decreasing cigarette nicotine level from 0.6 mg, to 0.3 mg, to 0.05 mg (Quest(r) step-down); or 3) smoke Quest(r) cigarettes in a non-step down random order, counter balanced across subjects (Quest(r) non-step- down). The study will consist of four stages beginning with a 5-day own brand cigarette smoking phase for all participants, followed by one of the three cigarette conditions. For those smoking Quest(r) cigarettes, cigarette nicotine level will change every 10 days, either in a step-down or random fashion. The primary behavioral outcome is smoking topography; specifically total and mean puff volume, which will be assessed at each session. Carbon monoxide to assess smoke exposure, and urinary biomarkers, will also be assessed. At baseline, participants will view Quest(r) advertisements and complete a survey of product expectations to determine the impact of beliefs about Quest(r) cigarettes on subsequent smoking behavior. This study has several important public health implications. It will determine how a new PREP is actually used. It will also determine how product use relates to harm exposure. Finally, it will identify those most susceptible to changes in smoking topography that may increase harm exposure.