Tirzepatide

ID: tirzepatide

Aliases: Mounjaro, Zepbound, TIRZEPATIDE

Type: compound

Route/form: subcutaneous injection

Status: approved

Evidence level: approved / labelled

Best data tier: approved label + human controlled/review

Support scope: human, context

Source types: company, human_physiology, human_rct, label, meta_analysis, systematic_review

Linked sources: 10

Broad outcomes: Fat loss / metabolic health, Muscle growth / performance / recovery

Reading note: These are curation notes anchored to linked sources, not a clinical recommendation or protocol.

Targets / mechanism

• GIP receptor agonist
• GLP-1 receptor agonist

Optimization domains

• metabolic
• obesity
• diabetes
• body composition
• GLP-1 adjunct

Research basis

• SURMOUNT obesity trials, population-specific SURMOUNT-CN data, and SURPASS diabetes trials support large weight-loss and glycemic effects for dual GIP/GLP-1 agonism.
• Human body-composition and appetite/energy-intake studies help separate fat-mass change from lean-mass change and explain the mechanism.
• Tirzepatide is now a reference comparator for myostatin/activin add-on trials like EMBRAZE, but those adjunct data should be treated separately from tirzepatide monotherapy.

Limits, risks, and missing evidence

• GI intolerance, gallbladder/pancreatitis warnings, dehydration/renal issues, and discontinuation weight regain remain practical constraints.
• Lean-mass loss and reduced energy intake matter for performance users; the drug is not directly anabolic.
• Diabetes, obesity, and adjunct-combination contexts should not be collapsed into one uniform body-composition claim.

Risk flags

• prescription
• metabolic endocrine
• medical supervision

Linked papers, labels, and reviews

1. Tirzepatide Once Weekly for the Treatment of Obesity
   human_rct / pubmed_tirzepatide_surmount1_2022
   SURMOUNT-1 trial.
2. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity
   human_rct / pubmed_tirzepatide_surmount4_2024
   SURMOUNT-4 randomized withdrawal/maintenance trial; direct human evidence that continued treatment maintains more weight loss than placebo withdrawal.
3. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study
   human_rct / pubmed_tirzepatide_surmount1_body_comp_2025
   DXA/body-composition substudy from SURMOUNT-1; relevant to fat-mass versus lean-mass interpretation.
4. Tirzepatide reduces appetite, energy intake, and fat mass in people with type 2 diabetes
   human_physiology / pubmed_tirzepatide_appetite_fatmass_2023
   Human mechanistic study connecting tirzepatide to reduced appetite/energy intake and fat mass.
5. Effect of glucagon-like peptide-1 receptor agonists and co-agonists on body composition
   meta_analysis / pubmed_glp1_body_composition_network_meta_2025
   Network meta-analysis comparing body-composition effects across GLP-1 receptor agonists and co-agonists.
6. DailyMed label: ZEPBOUND tirzepatide injection
   label / dailymed_zepbound_label
   Official tirzepatide obesity-label context for subcutaneous route, dose escalation, contraindications, GI/gallbladder/pancreatitis warnings, and related precautions.
7. Scholar Rock Reports Positive Phase 2 EMBRAZE Trial Results Demonstrating Statistically Significant Preservation of Lean Mass with Apitegromab During Tirzepatide-Induced Weight Loss
   company / businesswire_apitegromab_embraze_2025
   Sponsor-reported 24-week EMBRAZE phase 2 obesity results: apitegromab plus tirzepatide preserved more lean mass and shifted loss composition toward fat; not a peer-reviewed obesity paper at this curation point.
8. Tirzepatide for Weight Reduction in Chinese Adults With Obesity: The SURMOUNT-CN Randomized Clinical Trial
   human_rct / pubmed_tirzepatide_surmount_cn_2024
   Phase 3 obesity trial in Chinese adults; adds population-specific tirzepatide weight-loss and safety evidence.
9. Effect of Subcutaneous Tirzepatide vs Placebo Added to Titrated Insulin Glargine on Glycemic Control in Patients With Type 2 Diabetes: The SURPASS-5 Randomized Clinical Trial
   human_rct / pubmed_tirzepatide_surpass5_2022
   Phase 3 type 2 diabetes RCT with tirzepatide added to insulin glargine; supports glycemic and body-weight effects in insulin-treated T2D context.
10. Tirzepatide: A Systematic Update
    systematic_review / pubmed_tirzepatide_systematic_update_2022
    Systematic update across SURPASS trials and metabolic endpoints; useful for glycemic, lipid, blood-pressure, and safety context.