Tirzepatide for Smoking Cessation in people who smoke and are overweight or obese
Official title: A Multi-Site Trial of Tirzepatide for Smoking Cessation
Run by University of Southern California · NCT07602699 · Data updated 2026-11-12
This study tests whether tirzepatide can help adults who smoke quit and manage weight better than placebo when combined with usual smoking-cessation support.
Quick facts
| Phase | Phase 2 |
|---|---|
| Study type | Interventional |
| Ages | 21 Years to 65 Years |
| Sex | All |
| Enrollment | 300 (estimated) |
| Sponsor | University of Southern California Academic / other |
| Locations | 4 sites (Los Angeles, California and 3 other locations) |
| Status | Recruiting |
| Started | June 5, 2026 |
| Main results expected | March 2028 |
| Study ends | September 2028 |
| Registry record updated | July 17, 2026 |
| Trial ID | NCT07602699 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are adults 21–65 with BMI ≥25, who smoke ≥10 cigarettes daily, intend to quit within 1–2 months, and agree to receive study medication plus standard cessation supports.
✕Probably not a fit
Participants who do not want to quit smoking or who have BMI <25 or diabetes-related conditions may experience no benefit related to smoking cessation.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This is a multi-site, phase 2, randomized, placebo-controlled trial testing tirzepatide for smoking cessation in 300 adults who smoke and have BMI 25 or higher. Participants will be assigned to escalating doses of tirzepatide or placebo for 16 weeks, with weekly clinic visits and nicotine replacement therapy provided. All participants also receive standard cessation aids and a smoking-cessation app. The study will assess quitting success and changes in weight after cessation, with follow-up visits at weeks 17 and 27. The trial is conducted at four U.S. sites led by USC with collaboration from NIDA.
Why it matters
Potential benefit: If successful, tirzepatide could improve quit rates and help prevent post-cessation weight gain.
How similar studies have gone: Prior studies in related GLP-1 receptor agonists have shown promise for weight management and cessation support, but this exact tirzepatide approach for smoking cessation is exploratory.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: 1. Age 21-65 years 2. Body mass index ≥ 25kg/m2 at the baseline screening 3. Reporting ≥10 cigarettes per day, on average, for the past 6 months and \> 2 year duration of smoking 4. Interest in making a long-term cessation attempt within the next 30-60 days 5. Willingness to receive study medication and standard-of-care smoking cessation supports (nicotine replacement therapy and a smoking cessation app) 6. Ability to adhere to weekly visits and study procedures over the study period (i.e., no plans to move or travel for extended periods) 7. Exhaled CO of \>5ppm at baseline 8. Use of an acceptable birth control method for female participants\* 9. Ability to read and communicate in English Exclusion Criteria: 1. BMI \< 25 kg/m2 at screening 2. History of diabetes, diabetes-attributable medical conditions, or HbA1c ≥6.5% at baseline 3. Recent (past 90 days) active suicidal ideation or lifetime history of suicide attempt 4. Current treatment for psychotic disorders or mood disorders with psychotic features (e.g., schizophrenia, schizoaffective disorder, depression with psychotic features), current treatment for bipolar disorder (with or without psychotic features), or current secondary psychosis due to substance use or another medical condition 5. Meeting DSM-5 criteria for a current (past 12 months) substance use disorder other than tobacco use disorder, mild or moderate cannabis use disorder, or mild or moderate alcohol use disorder. 6. Recent (past 30 day) self-report of illicit drug use (excluding cannabis) or non-prescribed opioids; or positive urine screen for illicit drugs. A positive screen for opioids will be allowed if the participant is prescribed an opioid replacement therapy medication and can provide documentation. 7. Past 30-day initiation of psychiatric medications (e.g., SSRIs) or changes to medication dose 8. Treatment with tirzepatide or another GLP-1RA medication in the prior 6 months 9. Current (past month) treatment with other weight loss, diabetes, or smoking cessation medications (varenicline or bupropion; excluding nicotine replacement products) 10. Severe GI disease (e.g., gastroparesis, ulcerative colitis). 11. History of gastric bypass surgery or other surgeries of the stomach 12. Any health condition or treatment/medication that would preclude the use of tirzepatide or NRT, in the opinion of the study physician, including severe cardiovascular disease 13. History of chronic pancreatitis or acute pancreatitis in the last 6 months 14. Currently nursing, pregnant, or anticipating pregnancy 15. History of diabetic retinopathy, proliferative retinopathy, or maculopathy 16. Elevated serum lipase, amylase, bilirubin, or ALP, ALT, or AST (\>5x upper limit of normal range) 17. History of malignant neoplasms in the last 5 years, except non-melanoma skin cancer 18. Inability to attend weekly clinic visits as scheduled (i.e., based on travel or work schedule) 19. Currently enrolled in another clinical study involving an investigational product 20. Currently living in the same household as someone taking a GLP-1 medication, or living with a current or former participant in the present trial 21. Planned surgical procedures requiring anesthesia during the planned study medication period 22. Personal or family history of medullary thyroid cancer 23. Personal or family history of multiple endocrine neoplasia syndrome type 2 (MEN 2) 24. Treatment with other weight loss (e.g., phentermine), or FDA-approved, non-NRT smoking cessation therapies (varenicline, bupropion) or FDA-approved AUD medications (naltrexone, acamprosate, disulfiram) or off-label AUD medications (e.g., topiramate) in the past 90 days 25. Any health condition or treatment/medication that would preclude use of tirzepatide or NRT, in the opinion of the site physicians including thyroid enlargement.
Where it's running
-
Keck School of Medicine, University of Southern California
Los Angeles, California, United States Recruiting -
University of Colorado Anschutz Medical Campus
Aurora, Colorado, United States Recruiting -
Yale University School of Medicine
New Haven, Connecticut, United States Recruiting -
University of Chicago Pritzker School of Medicine
Chicago, Illinois, United States Recruiting
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.