title: Efficacy of the nicotine vaccine 3'-AmNic-rEPA (NicVAX) co-administered with varenicline and counselling for smoking cessation: a randomized placebo-controlled trial.
abstract: OBJECTIVE
  Nicotine vaccination has been proposed as a possible treatment to aid smoking cessation. First efficacy results of the nicotine vaccine 3'-AmNic-rEPA (NicVAX) showed that only a subgroup of the top 30% antibody responders achieved higher abstinence rates than placebo. The present study examined the efficacy of adding NicVAX versus placebo to varenicline and behavioural support as an aid in smoking cessation and relapse prevention.
  
  
  METHODS
  Randomized placebo-controlled trial.
  
  
  METHODS
  Two research centres (Maastricht University Medical Centre and Slotervaart Hospital) in the Netherlands.
  
  
  METHODS
  A total of 558 smokers were assigned randomly to six injections with NicVAX (n = 278) or placebo (n = 280) both co-administered with open label varenicline and behavioural support.
  
  
  METHODS
  Outcomes were prolonged carbon monoxide-validated abstinence from weeks 9 to 52 (primary) and weeks 37 to 52 (secondary). We also performed a pre-planned subgroup analysis in the top 30% antibody responders.
  
  
  RESULTS
  There was no difference in abstinence rates between NicVAX and placebo from weeks 9 to 52 [27.7 versus 30.0%, odds ratio (OR) = 0.89, 95% confidence interval (CI) = 0.62-1.29] or weeks 37 to 52 (33.8 versus 33.2%, OR = 1.03, 95% CI = 0.73-1.46). The top 30% antibody responders, compared to the placebo group, showed a non-significant tendency towards higher abstinence rates from weeks 37 to 52 (42.2 versus 33.2%, OR = 1.47, 95% CI = 0.89-2.42).
  
  
  CONCLUSIONS
  The nicotine vaccine, NicVAX, does not appear to improve the chances of stopping smoking when given in addition to varenicline and behavioural support.
authors.affiliation: CAPHRI School for Public Health and Primary Care, Department of Family Medicine, Maastricht University, Maastricht, the Netherlands.
authors.forename: Philippe H J
authors.initials: PH
authors.lastname: Hoogsteder
authors.forename: Daniel
authors.initials: D
authors.lastname: Kotz
authors.forename: Paul I
authors.initials: PI
authors.lastname: van Spiegel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Viechtbauer
authors.forename: Onno C P
authors.initials: OC
authors.lastname: van Schayck
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001552:Benzazepines / Q000627:therapeutic use*; D003376:Counseling / Q000379:methods* / Q000706:statistics & numerical data; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D018722:Nicotinic Agonists / Q000627:therapeutic use*; D011810:Quinoxalines / Q000627:therapeutic use*; D012008:Recurrence; D012907:Smoking / Q000188:drug therapy / Q000628:therapy*; D016540:Smoking Cessation / Q000379:methods* / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014612:Vaccines / Q000627:therapeutic use*; D000068580:Varenicline; D055815:Young Adult
chemical_list: D001552:Benzazepines; C557119:NicVAX; D018722:Nicotinic Agonists; D011810:Quinoxalines; D014612:Vaccines; D000068580:Varenicline
keywords: Efficacy; immunogenicity; nicotine vaccine; placebo; randomized; safety; trial