Published trial ladder

Retatrutide Phase 2 12 mg arm: published ladder and modeled levels

Updated by the GLP Ladder Editorial Team. Editorial policy.

Short answer

Retatrutide Phase 2 12 mg arm: 2/4/8/12 mg weekly, 4 weeks per step (Eli Lilly, hosted on ClinicalTrials.gov, Aug 29, 2022). The final 12 mg step begins in week 13. With t½ 6 days and R = 1.8033, the modeled amount peaks at 19.67 mg-eq. As published, not a recommendation; as of Oct 19, 2026.

Weeks per step
4 4 steps
Final step
12 mg from week 13
Modeled peak
19.67 mg-eq
Accumulation R
1.8033 t½ 6 d
Retatrutide Phase 2 12 mg arm: steps and modeled amountWeekly doses 2 mg, 4 mg, 8 mg, 12 mg; modeled amount peaks at 19.67 mg-equivalents.stable window06.2512.518.7525mg-eq0481216202428weeks from start2 mg4 mg8 mg12 mg
  • Weekly dose (published steps)
  • Modeled amount (mg-eq)
  • Stable window
Steps start on a Monday (Jan 5, 2026) for illustration. Curve: modeled relative amount, not plasma concentration. Open in the Retatrutide plotter to change dates or doses.
Phase 2 12 mg arm: weeks, weekly dose and dates from a Jan 5, 2026 start (Eli Lilly, hosted on ClinicalTrials.gov, Aug 29, 2022)
WeeksWeekly doseFirst week starts
1–4 2 mg Jan 5, 2026
5–8 4 mg Feb 2, 2026
9–12 8 mg Mar 2, 2026
13 onward 12 mg Mar 30, 2026

Weekly modeled amounts

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28 weeks. Highlighted rows start a new dose step. Model details: model card.

Retatrutide Phase 2 12 mg arm: weekly peak, trough and average (mg-equivalents)
WeekStartsDose mgPeakTroughAverage
1Jan 5, 202621.78201.287
2Jan 12, 202622.6080.9211.945
3Jan 19, 202622.9781.3312.238
4Jan 26, 202623.1441.5142.368
5Feb 2, 202644.9931.5953.713
6Feb 9, 202645.8572.5534.397
7Feb 16, 202646.2442.9794.701
8Feb 23, 202646.4173.1694.837
9Mar 2, 2026810.0433.2547.471
10Mar 9, 2026811.745.1338.814
11Mar 16, 2026812.55.9719.412
12Mar 23, 2026812.8386.3439.678
13Mar 30, 20261216.5356.5112.37
14Apr 6, 20261218.2688.42613.739
15Apr 13, 20261219.0439.27914.349
16Apr 20, 20261219.3889.65914.62
17Apr 27, 20261219.5429.82914.741
18May 4, 20261219.6119.90414.795
19May 11, 20261219.6419.93814.819
20May 18, 20261219.6559.95314.83
21May 25, 20261219.6619.95914.834
22Jun 1, 20261219.6649.96214.837
23Jun 8, 20261219.6659.96414.838
24Jun 15, 20261219.6659.96414.838
25Jun 22, 2026—10.3564.6357.118
26Jun 29, 2026—4.6132.0653.171
27Jul 6, 2026—2.0550.921.412
28Jul 13, 2026—0.9150.410.629

Sources

  1. Study Protocol J1I-MC-GZBF(b) for NCT04881760 (Prot_000.pdf). Eli Lilly and Company, hosted on ClinicalTrials.gov, Aug 29, 2022. Accessed Oct 19, 2026.
  2. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med 2023;389(6):514-526 (abstract via PubMed PMID 37366315; doi:10.1056/NEJMoa2301972), Jun 26, 2023. Accessed Oct 19, 2026.
  3. A Study of LY3437943 in Participants Who Have Obesity or Are Overweight (NCT04881760) - registry record with posted results. ClinicalTrials.gov (U.S. NLM), Sep 13, 2023. Accessed Oct 19, 2026.
  4. LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist in people with type 2 diabetes: a phase 1b, multicentre, double-blind, placebo-controlled, randomised, multiple-ascending dose trial. The Lancet 2022;400(10366):1869-1881 (abstract via PubMed PMID 36354040; doi:10.1016/S0140-6736(22)02033-5), Oct 27, 2022. Accessed Oct 19, 2026.

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