Tirzepatide weekly injections for weight loss in adults with obesity or overweight
Tests tirzepatide against placebo in adults with obesity or overweight, without diabetes.
Key facts
- Who runs it
- Hudson Biotech
- Where
- Shenzhen, ChinaSee the site
- Trial code
- Registry title
- Efficacy and Safety of Tirzepatide Once Weekly Versus Placebo in Participants Who Are Either Obese or Overweight With Weight-Related Comorbidities (SURMOUNT-1)
- Status
- Recruiting
- Phase
- Phase 3
- People taking part
- 2,539 people, planned
- Started
- 2 Feb 2026
- Expected to end
- 17 Mar 2028
- Type of study
- Interventional, 4 groups
- Treatments tested
- Tirzepatide
- Placebo
- Reduced-calorie diet
- Record updated
- 12 November 2026
Who can take part
AI summary
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults without diabetes who have obesity, or who are overweight and have a health problem linked to their weight. It compares weekly tirzepatide injections with placebo.
- Age
- 18 years or older
- Sex
- All sexes can join
- Disease stage
- BMI of 30 kg/m² or more, or BMI of 27 kg/m² or more with at least 1 weight-related health problem (for example high blood pressure, high cholesterol, sleep apnea, heart disease).
- Earlier treatment
- At least one earlier diet attempt to lose weight that did not work (self-reported). No weight-loss surgery, planned or past. No recent endoscopic or device-based obesity treatment.
Main reasons for not taking part
- Type 1 or type 2 diabetes
- Weight change of more than 5 kg (11 lb) in the 3 months before screening
- History of pancreatitis
- Personal or family history of medullary thyroid cancer or MEN2
- Severe kidney problems (eGFR below 30 mL/min/1.73 m²)
The registry criteria, word for word
Show all 19 criteriaShow less
Who can take part
- BMI ≥30 kg/m², OR BMI ≥27 kg/m² with ≥1 weight-related comorbidity (e.g., hypertension, dyslipidemia, obstructive sleep apnea, cardiovascular disease)
- History of at least one unsuccessful dietary effort to lose weight (self-reported)
- Investigator judges participant capable and willing to self-inject (or have assistance), follow lifestyle advice, maintain a diary, and complete questionnaires
- Age ≥18 years
- Meets protocol contraception/pregnancy criteria (as applicable) and provides written informed consent
Who cannot take part
- Recent significant weight change (>5 kg within 3 months prior to screening)
- Prior/planned bariatric surgery; recent/ongoing endoscopic or device-based obesity therapies
- Clinically significant gastric emptying abnormality or chronic use of drugs that directly affect GI motility
- Type 1 or type 2 diabetes, history of ketoacidosis/hyperosmolar state, or screening labs diagnostic of diabetes
- History of chronic or acute pancreatitis
- Obesity due to other endocrinologic disorders (e.g., Cushing syndrome) or monogenic/syndromic obesity (e.g., MC4R deficiency, Prader-Willi syndrome)
- Significant unstable major depressive disorder/severe psychiatric disorder, lifetime suicide attempt, or concerning suicidality screening (PHQ-9/C-SSRS criteria)
- Uncontrolled hypertension; recent major cardiovascular events; NYHA class IV heart failure
- Active or significant liver disease or certain elevated liver tests at screening (per protocol thresholds)
- Elevated calcitonin above protocol thresholds; personal/family history of medullary thyroid carcinoma or MEN2
- Any other condition contraindicating GLP-1 receptor agonist therapy
- Severe renal impairment (eGFR <30 mL/min/1.73 m²)
- Active/untreated malignancy or remission <5 years (with specified exceptions)
- Clinically significant thyroid abnormalities at screening (e.g., TSH outside protocol range) or anticipated need to initiate thyroid replacement during study
Where in China
- Peking University Shenzhen HospitalShenzhen, ChinaContact: Zhen J Peng, PhdTaking people
About the trial
What the trial wants to find out
This Phase 3 study evaluates the efficacy and safety of once-weekly subcutaneous tirzepatide (a dual GIP and GLP-1 receptor agonist) at 5 mg, 10 mg, or 15 mg versus placebo, each used with a reduced-calorie diet and increased physical activity, in adults without type 2 diabetes who have obesity or are overweight with weight-related comorbidities. The primary efficacy assessment is at Week 72. Participants with prediabetes at randomization may continue in an additional long-term treatment period to assess progression to type 2 diabetes and longer-term weight outcomes.
The 4 groups in the trial
- Arm 1: Tirzepatide 5 mg once weekly + lifestyle interventionTreatment being tested
Treatment: Tirzepatide, Placebo, and Reduced-calorie diet
- Arm 2: Tirzepatide 10 mg once weekly + lifestyle interventionTreatment being tested
Treatment: Tirzepatide, Placebo, and Reduced-calorie diet
- Arm 3: Tirzepatide 15 mg once weekly + lifestyle interventionTreatment being tested
Treatment: Tirzepatide, Placebo, and Reduced-calorie diet
- Arm 4: Placebo once weekly + lifestyle interventionTreatment being tested
Treatment: Tirzepatide, Placebo, and Reduced-calorie diet
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorData and sources
- Registry record
- Listed on ClinicalTrials.gov.
- Official title
- Efficacy and Safety of Tirzepatide Once Weekly in Participants Without Type 2 Diabetes Who Have Obesity or Are Overweight With Weight-Related Comorbidities: A Randomized, Double-Blind, Placebo-Controlled Trial (SURMOUNT-1)
- Plain-language title
- Tirzepatide weekly injections for weight loss in adults with obesity or overweightGenerated from the registry record. The registry title is the official one.
- AI summary
- From the trial's eligibility criteria. Read by machine on 13 November 2026.
- Record updated
- 12 November 2026