Efficacy and Safety of Tirzepatide Once Weekly Versus Placebo in Participants Who Are Either Obese or Overweight With Weight-Related Comorbidities (SURMOUNT-1)
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Tirzepatide, Placebo, Reduced-calorie diet.
- Who it may be relevant to
- Registry conditions: Obesity, Overweight (Without Type 2 Diabetes) With Weight-related Comorbidities. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- China
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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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)
Overview
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.
Detailed description
After screening, eligible participants are randomized in a 1:1:1:1 ratio to receive tirzepatide 5 mg, 10 mg, 15 mg, or placebo once weekly by subcutaneous injection using an autoinjector. All participants receive lifestyle counseling focused on a reduced-calorie diet and increased physical activity. The main treatment period is 72 weeks. Participants identified with prediabetes at randomization can continue study treatment for up to 176 weeks (plus follow-up), allowing evaluation of longer-term weight management and time to onset/progression to type 2 diabetes. Safety is monitored throughout, including adverse events and laboratory testing.
Interventions
- Drug Tirzepatide
(once-weekly SC injection; doses 5/10/15 mg) - Drug Placebo
(once-weekly SC injection) - Behavioral Reduced-calorie diet
increased physical activity counseling
Primary outcome measures
- Mean percent change in body weight from randomization [Time frame: 72 Weeks]
- Percentage of participants achieving ≥5% body weight reduction from randomization [Time frame: 72 Weeks]
Secondary outcome measures (2)
- Mean change in body weight [Time frame: 72 Weeks]
- Changes in cardiometabolic measures in triglycerides [Time frame: 72 weeks]
Eligibility 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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Double blind
- Primary purpose
- Treatment
Study locations
China · 1 center
- Peking University Shenzhen Hospital — Shenzhen
Identifiers
NCT: NCT07481747 · I8F-MC-GPHK(b)