Weight & body composition
Retatrutide vs Tirzepatide
Compare separate trial programmes with explicit cross-trial limitations; tirzepatide has authorised products while retatrutide remains investigational.
At a glance
Retatrutide
Tirzepatide
Human evidence
Randomized Phase II obesity data show major weight reduction. A 98-participant MASLD substudy also showed large dose-dependent liver-fat reductions, including >80% mean relative reduction at the two highest studied doses by week 24.
Large Phase III obesity evidence shows substantial weight loss. SURMOUNT-OSA additionally demonstrated large reductions in sleep-apnea severity in adults with obesity and moderate-to-severe OSA.
Research focus
Obesity, weight management, metabolic disease
Type 2 diabetes, obesity, weight management
Regulatory status
Not FDA-approved as of this review; FDA states retatrutide has not been found safe and effective for any condition and cannot be used in US compounding.
Tirzepatide is authorised in licensed products such as Mounjaro for type 2 diabetes and adult weight management in the EU; authorization is product- and jurisdiction-specific.
Route / formulation
Evidence applies to trial-grade retatrutide, not to unverified research-market vials or pens.
Unverified research-market material or non-authorised pens are not equivalent to licensed tirzepatide medicines merely because the active-ingredient name matches.
No direct head-to-head outcome trial identified Compare separate trial programmes with explicit cross-trial limitations; tirzepatide has authorised products while retatrutide remains investigational.