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Abstract Background Smokers need effective support to maximise the chances of successful quit attempts. Current smoking cessation medications, such as nicotine replacement therapy (NRT), bupropion, nortriptyline or varenicline, have been shown to be effective in clinical trials but are underused by smokers attempting to quit due to adverse effects, contraindications, low acceptability and/or high cost. Cytisine is a low-cost, plant-based alkaloid that has been sold as a smoking cessation aid in Eastern Europe for 50 years. A systematic review of trial evidence suggests that cytisine has a positive impact on both short- and long-term abstinence rates compared to placebo. However, the quality of the evidence is poor and insufficient for licensing purposes in many Western countries. A large, well-conducted placebo-controlled trial (n = 740) of cytisine for smoking cessation has recently been published and confirms the findings of earlier studies, with 12-month continuous abstinence rates of 8.4% in the cytisine group compared to 2.4% in the placebo group (Relative risk = 3.4, 95% confidence intervals 1.7-7.1). No research has yet been undertaken to determine the effectiveness of cytisine relative to that of NRT. Methods/design A single-blind, randomised controlled, non-inferiority trial has been designed to determine whether cytisine is at least as effective as NRT in assisting smokers to remain abstinent for at least one month. Participants (n = 1,310) will be recruited through the national telephone-based Quitline service in New Zealand and randomised to receive a standard 25-day course of cytisine tablets (Tabex®) or usual care (eight weeks of NRT patch and/or gum or lozenge). Participants in both study arms will also receive a behavioural support programme comprising an average of three follow-up telephone calls delivered over an eight-week period by Quitline. The primary outcome is continuous abstinence from smoking at one month, defined as not smoking more than five cigarettes since quit date. Outcome data will also be collected at one week, two months and six months post-quit date. Discussion Cytisine appears to be effective compared with placebo, and given its (current) relative low cost may be an acceptable smoking cessation treatment for smokers, particularly those in low- and middle-income countries. Cytisine's 'natural' product status may also increase its acceptability and use among certain groups of smokers, such as indigenous people, smokers in countries where the use of natural medicines is widespread (e.g. China, India), and in those people who do not want to use NRT or anti-depressants to help them quit smoking. However it is important to ascertain the effectiveness of cytisine compared with that of existing cessation treatments. Trial registration Australian New Zealand Clinical Trials Registry (ACTRN12610000590066)

Abstract Background Current smoking cessation treatments focus on addressing the pharmacological dependence of smokers on nicotine. However, new strategies are needed that address both nicotine dependence and the psychological dependence on cigarettes as the source of nicotine. Evidence from a number of small smoking cessation studies suggests that the use of cigarettes with reduced nicotine content, in combination with nicotine replacement therapy (NRT), may help reduce withdrawal symptoms and increase quit rates. This paper describes the protocol for a large randomised-controlled trial to test the effect of using nicotine-free cigarettes together with NRT on long-term quit rates. Methods/design This single-blind, randomised trial aims to recruit 1,410 participants through the national telephone-based Quitline service in New Zealand. Participants in the treatment arm will be asked to stop smoking nicotine-containing cigarettes on their chosen Quit day and smoke ad libitum nicotine-free (Quest 3) cigarettes for six weeks. At the same time people in this group will be asked to start using NRT patches, gum and/or lozenges (as recommended by Quitline) for eight weeks. Participants in the control arm will be asked to stop smoking completely on their chosen Quit day and start using NRT patches, gum and/or lozenges (as recommended by Quitline) for eight weeks. Data collection will occur at baseline, three and six weeks, and three and six months after Quit day. The primary outcome is the proportion of participants who self-report seven-day point prevalence abstinence at six months since Quit date. Discussion Smoking prevalence in New Zealand has changed little in recent years (particularly in Māori, the indigenous people of New Zealand) and additional options for smokers who want to quit are needed. Although a variety of methods are available to help, many are expensive, have side effects, and despite their use most quit attempts still fail. This trial will test the balance of benefits and risks of a new strategy for people to overcome nicotine dependence. Since smoking is the leading cause of lost healthy life years in New Zealand, if proven effective this strategy is likely to have substantial public health benefits. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12608000410358

A response from the authors of the article "Electronic cigarettes for smoking cessation: A randomised controlled trial," published in a 2013 issue of the journal is presented.

An antibody-based HIV-1 vaccine will require the induction of potent cross-reactive HIV-1-neutralizing responses. To demonstrate feasibility toward this goal, we combined vaccination targeting the fusion-peptide site of vulnerability with infection by simian-human immunodeficiency virus (SHIV). In four macaques with vaccine-induced neutralizing responses, SHIV infection boosted plasma neutralization to 45%-77% breadth (geometric mean 50% inhibitory dilution [ID 50 ] ∼100) on a 208-strain panel. Molecular dissection of these responses by antibody isolation and cryo-electron microscopy (cryo-EM) structure determination revealed 15 of 16 antibody lineages with cross-clade neutralization to be directed toward the fusion-peptide site of vulnerability. In each macaque, isolated antibodies from memory B cells recapitulated the plasma-neutralizing response, with fusion-peptide-binding antibodies reaching breadths of 40%-60% (50% inhibitory concentration [IC 50 ] < 50 μg/mL) and total lineage-concentrations estimates of 50-200 μg/mL. Longitudinal mapping indicated that these responses arose prior to SHIV infection. Collectively, these results provide in vivo molecular examples for one to a few B cell lineages affording potent, broadly neutralizing plasma responses., Competing Interests: Declaration of interests The authors declare no competing interests., (Published by Elsevier Inc.)