Cytisine versus nicotine for smoking cessation

Area of Science:

• Pharmacology
• Public Health
• Clinical Trials

Background:

• Cytisine, a partial agonist of nicotinic acetylcholine receptors, is a smoking cessation aid with demonstrated efficacy.
• Previous placebo-controlled trials suggest cytisine nearly doubles smoking cessation rates at six months.
• This study aimed to compare the effectiveness of cytisine against nicotine-replacement therapy (NRT) for smoking cessation.

Purpose of the Study:

• To determine if cytisine is non-inferior to nicotine-replacement therapy (NRT) in aiding smokers to quit.
• To evaluate the comparative effectiveness of cytisine versus NRT in a real-world setting.

Main Methods:

• A pragmatic, open-label, noninferiority trial was conducted in New Zealand with 1310 adult smokers motivated to quit.
• Participants were randomized to receive either 25 days of cytisine or 8 weeks of NRT, with both groups receiving telephone-delivered behavioral support.
• The primary outcome measured was self-reported continuous smoking abstinence at one month.

Main Results:

• At one month, continuous abstinence rates were 40% for cytisine and 31% for NRT, indicating cytisine's superiority (9.3 percentage point difference).
• Cytisine demonstrated superior effectiveness over NRT at one week, two months, and six months.
• Adverse events were more frequent with cytisine (primarily nausea, vomiting, sleep disorders) than with NRT.

Conclusions:

• Cytisine, when combined with brief behavioral support, is superior to nicotine-replacement therapy for smoking cessation.
• Despite its superior efficacy, cytisine use is associated with a higher incidence of self-reported adverse events.
• The findings support cytisine as a more effective smoking cessation option, though patient counseling regarding side effects is warranted.