Aggregated from the cited literature below. We summarize sources — we don't author claims.
Tirzepatide is described in the provided sources as a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. Multiple phase 3 randomized clinical trials evaluated tirzepatide in adults with obesity (SURMOUNT-1, -4), obesity with type 2 diabetes (SURMOUNT-2), obstructive sleep apnea with obesity (SURMOUNT-OSA), and heart failure with preserved ejection fraction with obesity (SUMMIT).
Mechanism (as reported)
Across sources, tirzepatide is described as a dual GIP and GLP-1 receptor agonist; one review additionally describes effects on gastric emptying (GE), including substantial delay after the first dose and tachyphylaxis after subsequent doses. (PMID 35658024; PMID 34170647; PMID 37385275; PMID 38912654; PMID 37940101; PMID 35658024)
Key findings (each cites a source)
A phase 3 randomized withdrawal trial (SURMOUNT-4) reported that withdrawing tirzepatide led to substantial regain of lost weight, while continued tirzepatide maintained and augmented initial weight reduction through week 88; the mean percent weight change from week 36 to week 88 was -5.5% with continued tirzepatide vs 14.0% with placebo, and 89.5% vs 16.6% maintained at least 80% of lead-in weight loss. (PMID 38078870) [PMID 38078870]
In a phase 3 trial in adults with obesity (SURMOUNT-1), tirzepatide produced greater weight reductions at week 72 than placebo, and the most common adverse events were gastrointestinal, mostly mild to moderate and occurring primarily during dose escalation. (PMID 35658024) [PMID 35658024]
In a phase 3 analysis of SURMOUNT-1 participants with obesity and prediabetes over 176 weeks, fewer participants were diagnosed with type 2 diabetes in tirzepatide groups than in placebo, and no new safety signals were identified; gastrointestinal adverse events were common and mostly mild to moderate. (PMID 39536238) [PMID 39536238]
In a phase 3 trial in adults with obesity and type 2 diabetes (SURMOUNT-2), tirzepatide 10 mg and 15 mg resulted in greater bodyweight reductions at week 72 than placebo, and the most frequent adverse events were gastrointestinal-related (nausea, diarrhoea, vomiting) that were mostly mild to moderate, with fewer events leading to discontinuation (<5%). (PMID 37385275) [PMID 37385275]
In two phase 3 randomized controlled trials in adults with moderate-to-severe obstructive sleep apnea and obesity (SURMOUNT-OSA), tirzepatide reduced the apnea-hypopnea index (AHI) at week 52 compared with placebo and improved multiple prespecified secondary endpoints; reported adverse events were mostly gastrointestinal and mostly mild to moderate. (PMID 38912654) [PMID 38912654]
In an international randomized placebo-controlled trial in heart failure with preserved ejection fraction and obesity (SUMMIT), a composite endpoint of adjudicated cardiovascular death or worsening heart-failure event occurred less often with tirzepatide than placebo, and health status (KCCQ-CSS) improved at 52 weeks; discontinuation due to adverse events occurred in 6.3% with tirzepatide vs 1.4% with placebo, mainly due to gastrointestinal adverse events. (PMID 39555826) [PMID 39555826]
A literature review assessing impacts of tirzepatide and GLP-1 receptor agonists on oral hormonal contraception reported that one of six included clinical trials (involving tirzepatide) showed a statistically significant reduction in area under the plasma drug concentration-time curve (AUC), maximum concentration (Cmax), and time to Cmax when tirzepatide was concomitantly administered with an oral hormonal contraceptive; the remaining five studies involving GLP-1 receptor agonists did not show statistically or clinically significant differences. (PMID 37940101) [PMID 37940101]
In an open-label phase 3 trial comparing tirzepatide with semaglutide in patients with type 2 diabetes (SURPASS-2), tirzepatide groups had greater reductions in body weight than semaglutide, with the most common adverse events being gastrointestinal and reported as primarily mild to moderate in severity. (PMID 34170647) [PMID 34170647]
Vendor test rankings (8)
Vendors ranked by their independent third-party test grade for Tirzepatide, attributed to Finnrick. The grade is their verdict, not ours.
Real third-party HPLC results aggregated from Peptigrity, each attributed to the lab that ran it — average purity 99.7% across 810 tests. Not our verdict.
Frías JP, Davies MJ, Rosenstock J, Pérez Manghi FC, Fernández Landó L, Bergman BK · The New England journal of medicine · 2021 · PMID 34170647
FAQ
What is Tirzepatide?
Tirzepatide (2023788-19-2, Mounjaro (TN), Zepbound (TN)) is classified under glp-1 & incretin agonists, an FDA-approved drug. Research goals associated with it include metabolic & weight.
Is Tirzepatide FDA-approved?
Yes — Tirzepatide is approved by the FDA (marketed as 2023788-19-2, Mounjaro (TN)).
What does the research on Tirzepatide say?
peptideone aggregates 10 references from PubMed for Tirzepatide. The summary on this page digests them with citations; we summarize sources and make no efficacy claims.