Tirzepatide vs Retatrutide: Trial Data, Approval Status
Tirzepatide is FDA approved and sold now; Retatrutide is not FDA approved and is only available in trials. Tirzepatide is approved for type 2 diabetes, sleep apnea, heart risk, and weight loss.
A quick look at Zepbound
The half-life is 5 to 6 days. Half clears after 5.5 d, and five half-lives leave about 3% at 27.5 d.
In SURMOUNT-1, 72 weeks, body weight fell 20.9% compared with 3.1% on placebo.
Monthly prices are in US dollars. They include the list price and self-pay offers, all taken from the maker's price page.
Sources: FDA label (DailyMed), Eli Lilly 1 2, cnbc.com.
Retatrutide and Tirzepatide side by side
| Tirzepatide | Retatrutide | |
|---|---|---|
| Active ingredient | tirzepatide | Not listed |
| Manufacturer | Eli Lilly | Eli Lilly |
| How it is taken | Weekly injection | Not listed |
| Approved for | Type 2 diabetes, sleep apnea, heart risk, and weight loss | Not listed |
| First FDA approval | 2022 | Not listed |
| Average weight loss in trials | 20.9% (SURMOUNT-1, 72 weeks) | Not listed |
| Most common side effect | Nausea 18% vs 4% on placebo | Not listed |
| List price | $1,112.16 per fill | Not listed |
| Self-pay from | $299 per month | Not listed |
| Medicare GLP-1 Bridge | $50 per month, eligible Part D | Not listed |
| FDA shortage | Resolved December 19, 2024 | Not listed |
| Weight loss pct | Not listed | 22.6% |
| Weeks | Not listed | 80 weeks |
| Expected | Not listed | BLA submission Q1 2027 |
| Expected approval | Not listed | BLA submission Q1 2027 |
Sources: FDA label, FDA label (DailyMed), pricinginfo.lilly.com, TrumpRx.
Prices and coverage compared
| Medicine | How you pay | Price |
|---|---|---|
 Mounjaro | List price before insurance | $1,112.16 per fill |
| Mounjaro | Mounjaro Savings Card (insured) | from $25 for up to a 3-month fill |
| Mounjaro | Commercial plan that does not cover it | $499 per month |
 Zepbound | List price before insurance | $499 to $1,086 per fill |
| Zepbound | Zepbound Savings Program (insured) | from $25 for up to a 3-month fill |
| Zepbound | Commercial plan that does not cover it | $299 per month |
| Zepbound | Self-pay: LillyDirect vial or KwikPen 2.5 mg | $299 per month |
| Zepbound | Self-pay: LillyDirect vial or KwikPen 5 mg | $399 per month |
| Zepbound | For LillyDirect self-pay, the refill window is 45 days, and doses range from 7.5 mg through 15 mg | $449 per month |
| Zepbound | Self-pay: The regular price applies if it is not refilled within 45 days | per month, the cost is $499 ($7.5 mg) or $699 ($10 to $15 mg) |
| Zepbound | Self-pay via TrumpRx | $299 per month |
| Zepbound | Medicare GLP-1 Bridge (Zepbound KwikPen, eligible Part D) | $50 per month |
Prices checked November 2026 (7)
pricinginfo.lilly.com 1 2, mounjaro.lilly.com, zepbound.lilly.com, Eli Lilly, TrumpRx, CMS.
Where Retatrutide stands
| Retatrutide | |
|---|---|
| Weight loss pct | 22.6% |
| Weeks | 80 weeks |
| Expected | BLA submission Q1 2027 |
| Expected approval | BLA submission Q1 2027 |
Source: prnewswire.com.