Corresponding Author: Ryan J. Courtney, PhD, National Drug and Alcohol Research Centre, University of New South Wales, R1 Building, 22-32 King St, Randwick, NSW, Australia (r.courtney@unsw.edu.au).
Accepted for Publication: April 28, 2021.
Author Contributions: Drs Courtney and Farrell had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Concept and design: Courtney, McRobbie, Tutka, Petrie, Shakeshaft, Thomas, Walker, Gartner, Mattick, Paul, Ferguson, Zwar, Richmond, Doran, Boland, Hall, West, Farrell.
Acquisition, analysis, or interpretation of data: Courtney, McRobbie, Weaver, Petrie, Mendelsohn, Shakeshaft, Talukder, Macdonald, Thomas, Kwan, Walker, Paul, Ferguson, Doran, Farrell.
Drafting of the manuscript: Courtney, McRobbie, Tutka, Petrie, Kwan, Walker, Ferguson, Doran, Farrell.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Courtney, Weaver, Petrie.
Obtained funding: Courtney, McRobbie, Petrie, Shakeshaft, Walker, Gartner, Mattick, Paul, Ferguson, Richmond, Doran, Farrell.
Administrative, technical, or material support: Courtney, McRobbie, Shakeshaft, Talukder, Macdonald, Thomas, Kwan, Mattick, Ferguson, Richmond, Boland, Farrell.
Supervision: Courtney, McRobbie, Tutka, Thomas, Kwan, Mattick, Paul, Ferguson, Richmond, Boland, Farrell.
Conflict of Interest Disclosures: Dr McRobbie reported receiving honoraria from Pfizer for speaking at smoking cessation meetings and attending advisory board meetings. Drs McRobbie and Walker reported previously receiving cytisine from Sopharma for the conduct of a noninferiority trial of cytisine vs nicotine replacement therapy. Dr Tutka reported serving as consultant to Aflofarm, which is a manufacturer of cytisine. Dr Mendelsohn reported receiving funding from Pfizer Australia, GlaxoSmithKline, and Johnson & Johnson Pacific for teaching, consulting, serving on an advisory board, and conference expenses. Dr Kwan reported receiving speaking fees from Pfizer. Dr Walker reported receiving cytisine from Achieve Life Sciences for the conduct of a noninferiority trial of cytisine (Tabex) vs varenicline; receiving investigator-initiated grants and smoking cessation medication (varenicline) and matching placebo from Pfizer for the conduct of a relapse prevention trial in patients with chronic obstructive pulmonary disease who smoke; and serving as a consultant for and receiving honoraria and travel support for speaking at research meetings from Achieve Life Sciences and Pfizer (manufacturers of smoking cessation medications). Dr Gartner reported receiving grants from the Australian Research Council, Metro South Health Service, Central Queensland Hospital and Health Service, Arthritis Australia, and the HIV Foundation Queensland. Dr Ferguson reported previously serving as a consultant to Pfizer and GlaxoSmithKline Consumer Healthcare on matters relating to smoking cessation and harm minimization; having been a member of a scientific advisory board for Johnson & Johnson; receiving researcher-initiated project grant funding from Pfizer (through the Grand initiative); and having provided consulting services to JUUL Labs Inc while working as a consultant for Pinney Associates. Dr Zwar reported receiving honoraria from Pfizer and GlaxoSmithKline for advice on smoking cessation education programs and for conference expenses. Dr West reported serving as a consultant to Pfizer, which manufactures varenicline, and receiving grants from Pfizer. Dr Farrell reported receiving unrestricted research funding from Mundipharma, Seqirus, and Indivior. No other disclosures were reported.
Funding/Support: This research was funded by project grant 1108318 and career development fellowship grant 1148497 (awarded to Dr Courtney) from the Australian National Health and Medical Research Council. The University of New South Wales National Drug and Alcohol Research Centre is supported by grant funding from the Australian government under the Substance Misuse Prevention and Service Improvements Fund. All study medications were purchased by the research team.
Role of the Funder/Sponsor: The funders/sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Data Sharing Statement: See Supplement 4.
Additional Contributions: We thank the study participants, the individuals at the social research center who conducted the baseline and follow-up interviews, the individuals at the Chemist Warehouse pharmacy for storing and dispensing medications (central pharmacy), Josephine Pang, MBBS (compensated study physician), staff at the University of New South Wales trial coordinating center, and the uncompensated data and safety monitoring board members (Julia Lappin, PhD, Jason Grebely, PhD, and Kathy Petoumenos, PhD [all 3 with the University of New South Wales], and Daniel Barker, PhD [University of Newcastle]). We also thank Mohammad Siahpush, PhD (University of Nebraska Medical Center), for uncompensated contributions to the overall trial and for input on the statistical analysis plan, and Alan Melrose, LLB (University of New South Wales), for uncompensated support with other trial-related inquiries.
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