Both are GLP-1 receptor agonists. Beyond that they differ in molecule, FDA indication, dose ceiling, and — most importantly to most people reading this — what the scale actually does over the long run.
Semaglutide
Tirzepatide
Different molecules, different indications. Ozempic is sema for diabetes; Zepbound is tirzepatide for obesity. If you don't have T2D, Zepbound is the on-label option. If you have T2D and your goal is weight loss, the prescribing question is usually Mounjaro vs. Ozempic, not Ozempic vs. Zepbound — but the molecule comparison is informative either way.
Molecule
OzempicSemaglutide
ZepboundTirzepatide
Receptor(s)
OzempicGLP-1
ZepboundGIP + GLP-1 (dual agonist)
Manufacturer
OzempicNovo Nordisk
ZepboundEli Lilly
FDA approval
OzempicDecember 2017
ZepboundNovember 2023 (obesity); December 2024 (obstructive sleep apnea in obesity)
Indication
OzempicType 2 diabetes (with later cardiovascular and CKD indications)
ZepboundChronic weight management; OSA in adults with obesity (added Dec 2024)
Delivery
OzempicSubcutaneous injection, once weekly
ZepboundSubcutaneous injection, once weekly
Dose ceiling
Ozempic2.0 mg weekly
Zepbound15 mg weekly
Titration
Ozempic4 weeks per step
Zepbound4 weeks per step
Typical loss
Ozempic~6% body weight at 6–12 months in T2D patients; ~10–13% in non-diabetic off-label use at higher doses
Zepbound~20.9% mean body weight at 72 weeks in SURMOUNT-1 (15 mg arm) vs. 3.1% placebo; ~26.6% in SURMOUNT-3 (with intensive lifestyle); ~23% in SURMOUNT-5 head-to-head vs. semaglutide (vs. ~15%)
Cash list
Ozempic$950–$1,350
Zepbound$1,060 list; $499–$649 via LillyDirect self-pay vials (2024+)
On patent until
Ozempic2031 (US composition of matter)
Zepbound2036 (US)