Tobacco research methodology: first things first

Study protocol for a randomised controlled trial of electronic cigarettes versus nicotine patch for smoking cessation

Background

Electronic cigarettes (e-cigarettes or electronic nicotine delivery systems [ENDS]) are electrically powered devices generally similar in appearance to a cigarette that deliver a propylene glycol and/or glycerol mist to the airway of users when drawing on the mouthpiece. Nicotine and other substances such as flavourings may be included in the fluid vaporised by the device. People report using e-cigarettes to help quit smoking and studies of their effects on tobacco withdrawal and craving suggest good potential as smoking cessation aids. However, to date there have been no adequately powered randomised trials investigating their cessation efficacy or safety. This paper outlines the protocol for this study.

Methods/design

Design: Parallel group, 3-arm, randomised controlled trial. Participants: People aged ≥18 years resident in Auckland, New Zealand (NZ) who want to quit smoking. Intervention: Stratified blocked randomisation to allocate participants to either Elusion™ e-cigarettes with nicotine cartridges (16 mg) or with placebo cartridges (i.e. no nicotine), or to nicotine patch (21 mg) alone. Participants randomised to the e-cigarette groups will be told to use them ad libitum for one week before and 12 weeks after quit day, while participants randomised to patches will be told to use them daily for the same period. All participants will be offered behavioural support to quit from the NZ Quitline. Primary outcome: Biochemically verified (exhaled carbon monoxide) continuous abstinence at six months after quit day. Sample size: 657 people (292 in both the nicotine e-cigarette and nicotine patch groups and 73 in the placebo e-cigarettes group) will provide 80% power at p = 0.05 to detect an absolute difference of 10% in abstinence between the nicotine e-cigarette and nicotine patch groups, and 15% between the nicotine and placebo e-cigarette groups.

Discussion

This trial will inform international debate and policy on the regulation and availability of e-cigarettes. If shown to be efficacious and safe, these devices could help many smokers as an alternative smoking cessation aid to standard nicotine products.

Trial registration

Australian NZ Clinical Trials Registry (ACTRN12610000866000).

Tobacco and nicotine product testing

INTRODUCTION

Tobacco product testing is a critical component of the Family Smoking Prevention and Tobacco Control Act (FSPTCA), which grants the Food and Drug Administration the authority to regulate tobacco products. The availability of methods and measures that can provide accurate data on the relative health risks across types of tobacco products, brands, and subbrands of tobacco products on the validity of any health claims associated with a product, and on how consumers perceive information on products toxicity or risks is crucial for making decisions on the product's potential impact on public health. These tools are also necessary for making assessments of the impact of new indications for medicinal products (other than cessation) but more importantly of tobacco products that may in the future be marketed as cessation tools.

OBJECTIVE

To identify research opportunities to develop empirically based and comprehensive methods and measures for testing tobacco and other nicotine-containing products so that the best science is available when decisions are made about products or policies.

METHODS

Literature was reviewed to address sections of the FSPTCA relevant to tobacco product evaluation; research questions were generated and then reviewed by a committee of research experts.

RESULTS

A research agenda was developed for tobacco product evaluation in the general areas of toxicity and health risks, abuse liability, consumer perception, and population effects.

CONCLUSION

A cohesive, systematic, and comprehensive assessment of tobacco products is important and will require building consensus and addressing some crucial research questions.