A major US clinical trial is testing whether tirzepatide could help people stop smoking while tackling one of the concerns that sometimes accompanies quitting: weight gain.
The Phase 2 study is recruiting 300 treatment-seeking smokers with a BMI of at least 25 kg/m² across the University of Southern California, Yale University, the University of Chicago, and the University of Colorado Anschutz Medical Campus. Participants will receive either tirzepatide or placebo for 16 weeks, with the dose gradually increasing from 2.5 mg to 10 mg weekly. Importantly, everyone will also receive nicotine patches.
Researchers will assess smoking cessation alongside outcomes including post-cessation weight gain, with follow-up extending to week 27. The trial is expected to be completed in 2028.
Although results are years away, the study illustrates an increasingly important principle: helping people quit smoking may require more than one route.
Different paths leading to smoking cessation
Tirzepatide is better known for its use in type 2 diabetes and obesity than tobacco dependence. Its investigation for smoking therefore adds another potential approach to an expanding cessation toolbox.
For tobacco harm reduction advocates, that flexibility is significant. Some smokers succeed with nicotine patches or prescription medicines; others stop without assistance, while increasing numbers switch to non-combustible nicotine products.
The latest Cochrane living review, including 90 completed studies and involving more than 29,000 participants, added to the evidence for the latter approach. Its 2026 update found high-certainty evidence that nicotine e-cigarettes produce higher quit rates than conventional nicotine replacement therapy, equivalent to around four additional quitters per 100 people. This reinforces the argument that cessation policy should focus primarily on helping people stop smoking rather than insisting that every smoker follow the same route to nicotine abstinence.
Do Smokers Understand What Makes Cigarettes Deadly?
One obstacle is widespread confusion over the source of smoking-related harm. A 2023 PLOS One study involving 12,904 current and recent former smokers in England, the US, Canada and Australia found that only 4% correctly assessed the relative contribution of combustion, nicotine, tobacco constituents and additives to smoking-related disease. Only around one-quarter clearly recognised combustion as substantially more important than nicotine.
Those who understood that combustion contributes much more to harm than nicotine were less likely to be daily smokers and more likely to have quit or be vaping. Because the research was observational, it cannot show that better knowledge caused those behavioural differences. Nevertheless, the association raises an important communication question.
Cigarette warnings repeatedly tell smokers that smoking kills, but rarely explain why. Burning tobacco generates many of the toxicants responsible for smoking-related cancers, cardiovascular disease and respiratory illness. Nicotine creates dependence and carries risks of its own, but separating nicotine delivery from combustion can dramatically alter toxicant exposure.
Clearer communication about this distinction could help smokers understand why completely switching to a non-combustible alternative is different from continuing to smoke.
Growing regulatory contradictions
That distinction has become particularly relevant as governments take increasingly different approaches to other psychoactive substances. In a September 2026 Harm Reduction Journal paper, researcher Konstantinos Farsalinos describes what he calls the “Cannabis Green Wave” versus the “Nicotine Freeze.” His argument is that governments are increasingly accepting harm reduction, adult autonomy and regulated markets for cannabis while moving towards tighter restrictions on non-combustible nicotine products.
Farsalinos points out that cigarettes remain legally available in countries that prohibit vaping products, creating what he regards as a regulatory inversion: the most hazardous nicotine delivery system remains accessible while alternatives that eliminate cigarette combustion can be restricted.
His analysis also highlights a lesson increasingly accepted in cannabis policy—prohibition does not work. It does not eliminate demand and tends to instead transfer supply to illicit markets. Applying that conclusion to nicotine remains controversial, but experiences with illegal vaping markets provide reasons to investigate it rather than assume prohibition automatically prevents use.
It should be about quitting smoking, not quitting nicotine
None of these developments suggests abandoning conventional tobacco control. Preventing youth initiation, enforcing age restrictions, supporting smoke-free environments and expanding access to proven cessation treatments remain important. Nor should nicotine vaping, tirzepatide, patches or prescription medications be presented as universally appropriate solutions.
Instead, the emerging evidence points towards a broader objective: give people who smoke multiple credible ways to leave combustible cigarettes behind. The tirzepatide trial embodies that approach. Researchers are not asking participants to quit nicotine immediately; they are giving everyone nicotine patches while testing whether another medication improves cessation and limits weight gain.
The same pragmatism could inform wider nicotine policy. Science keeps giving us high-certainty evidence that vaping can outperform NRT for cessation, while research shows that many smokers still misunderstand the fundamental role combustion plays in cigarette harm. The future of smoking cessation may therefore depend less on finding a single perfect method than on accepting that different smokers need different exits. Whether that means medication, nicotine replacement, vaping or eventually drugs such as tirzepatide, the immediate public-health priority remains the same: help people stop inhaling cigarette smoke.
