Once-weekly tirzepatide injections for adults with obesity or overweight and weight-related conditions
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)
This trial will see if once-weekly tirzepatide injections (5 mg, 10 mg, or 15 mg) plus a reduced-calorie diet and increased activity help adults with obesity or overweight (without diabetes) lose and keep off weight compared with placebo.
Quick facts
| Phase | Phase 3 |
|---|---|
| Study type | Interventional |
| Enrollment | 2539 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Hudson Biotech Industry-sponsored |
| Locations | 1 site (Shenzhen, Guangdong) |
| Trial ID | NCT07481747 on ClinicalTrials.gov |
What this trial studies
Adults aged 18 or older without type 2 diabetes who have a BMI ≥30 kg/m² or BMI ≥27 kg/m² with at least one weight-related comorbidity are randomized 1:1:1:1 to receive once-weekly subcutaneous tirzepatide (5, 10, or 15 mg) or placebo using an autoinjector, with all participants receiving counseling on a reduced-calorie diet and increased physical activity. The main treatment period is 72 weeks and the primary efficacy assessment occurs at Week 72. Participants with prediabetes at randomization may continue treatment for up to 176 weeks to evaluate longer-term weight outcomes and time to onset or progression to type 2 diabetes. Safety is monitored throughout the trial with regular adverse event reporting and laboratory tests.
Who should consider this trial
Good fit: Adults ≥18 years with BMI ≥30 kg/m², or BMI ≥27 kg/m² with at least one weight-related comorbidity, who do not have type 1 or type 2 diabetes and who can self-inject (or have assistance) and follow lifestyle counseling are appropriate candidates.
Not a fit: People with type 1 or type 2 diabetes, recent major weight change, prior or planned bariatric surgery, severe renal impairment, significant gastric emptying abnormalities, or who cannot comply with injections and protocol requirements are unlikely to benefit from this intervention.
Why it matters
Potential benefit: If successful, tirzepatide could produce substantial and sustained weight loss and reduce the risk of progression to type 2 diabetes in people with overweight or obesity.
How similar studies have performed: Previous tirzepatide trials in people with type 2 diabetes and earlier obesity trials, together with positive results from other GLP‑1–based therapies, have demonstrated substantial weight loss, so this approach has supporting prior data.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * 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 Exclusion Criteria: * Type 1 or type 2 diabetes, history of ketoacidosis/hyperosmolar state, or screening labs diagnostic of diabetes * Recent significant weight change (\>5 kg within 3 months prior to screening) * Prior/planned bariatric surgery; recent/ongoing endoscopic or device-based obesity therapies * Severe renal impairment (eGFR \<30 mL/min/1.73 m²) * Clinically significant gastric emptying abnormality or chronic use of drugs that directly affect GI motility * History of chronic or acute pancreatitis * Clinically significant thyroid abnormalities at screening (e.g., TSH outside protocol range) or anticipated need to initiate thyroid replacement during study * 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 * Active/untreated malignancy or remission \<5 years (with specified exceptions) * Any other condition contraindicating GLP-1 receptor agonist therapy
Where this trial is running
Shenzhen, Guangdong
- Peking University Shenzhen Hospital — Shenzhen, Guangdong, China (Recruiting)
Study contacts
- Study coordinator: Seni S Lu, Phd
- Email: Seni-Lu@beijing-biotech.com
- Phone: +86 13076790030
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.