Notice: Retatrutide is investigational and NOT FDA-approved. Educational content only. Not medical advice. Consult your physician.
We track FDA milestones daily. Bookmark this page. Retatrutide (Eli Lilly LY3437943) is currently investigational and NOT FDA-approved. Status reflects the latest publicly available trial registry and Eli Lilly disclosures.
Last verified against ClinicalTrials.gov NCT05882045 (TRIUMPH-4). Estimated dates are projections, not guarantees.
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Current approval process status
Phase 2
Completed · 2023
~24% loss at 48 wk (NEJM)
Phase 3 (TRIUMPH)
IN PROGRESS · 2026
TRIUMPH-4: 28.7% loss
NDA Submission
Estimated · Q4 2026 / Q1 2027
Lilly files with FDA
FDA AdCom
Estimated · 2027
Advisory Committee review
FDA Approval
Estimated · 2027–2028
Commercial availability
Key event: Jastreboff et al. published the Phase 2 obesity trial in The New England Journal of Medicine in 2023. Mean weight loss at the highest dose reached approximately 24.2% over 48 weeks — the largest reduction observed for a non-bariatric obesity drug at that time.
What this means for patients: Phase 2 confirmed that the triple-agonist mechanism (GLP-1 + GIP + glucagon) produces materially larger weight reduction than dual-agonist tirzepatide at comparable durations, with a manageable side-effect profile dominated by GI symptoms.
Source: Jastreboff AM, et al. NEJM. 2023;389(6):514-526. PubMed PMID: 37364103.
Key event: Eli Lilly's TRIUMPH program runs five Phase 3 trials. TRIUMPH-4 (long-term efficacy) reported topline results in 2025: approximately 28.7% mean weight loss at 76 weeks at the highest dose — the highest reported in any Phase 3 obesity trial. TRIUMPH-CVOT (cardiovascular outcomes) remains ongoing.
What this means for patients: Phase 3 readouts are the data the FDA will rely on for approval. Each new readout (efficacy, safety, durability, cardiovascular) tightens or loosens the projected approval window. Full peer-reviewed publications of TRIUMPH trials are expected throughout 2026.
Source: ClinicalTrials.gov NCT05882045 (TRIUMPH-4); Eli Lilly investor disclosures, 2024–2025. Full peer-review publication pending.
Key event: Eli Lilly is expected to submit the New Drug Application (NDA) to the FDA in late 2026 or early 2027, contingent on the full TRIUMPH-1, -2, -3, and -4 packages. The NDA formally starts the FDA review clock.
What this means for patients: The day Lilly files the NDA, the FDA has 60 days to accept the filing and assign a PDUFA decision date — typically 10 months later for standard review or 6 months under priority review. That PDUFA date becomes the strongest single signal of when retatrutide could reach pharmacies.
Source: Eli Lilly Q4 2025 earnings commentary (publicly available); FDA PDUFA review framework. Submission timing remains an estimate, not a promise.
Key event: The FDA may convene an Endocrinologic and Metabolic Drugs Advisory Committee (EMDAC) to publicly review the retatrutide package. The committee votes on benefit/risk; the FDA is not bound by the vote, but historically follows it.
What this means for patients: An AdCom hearing is a public, transcribed event. It is the first time outside experts and patient representatives publicly scrutinize the data. Materials are released to the public 48 hours before the meeting — usually a strong predictor of approval probability.
Source: FDA Advisory Committee historical pattern for prior obesity drug approvals (Wegovy, Zepbound). AdCom may or may not be required for retatrutide.
Key event: The FDA issues an approval letter (or Complete Response Letter requesting more data) by the PDUFA date. Approval is the moment retatrutide becomes legally prescribable in the United States.
What this means for patients: Commercial availability typically follows approval within weeks once Lilly has manufacturing capacity ready. Pricing, formulary placement, and prior-authorization criteria are usually announced in the same window. Subscribers to the FDA alert list get an email within hours of the announcement.
Source: FDA approval pathway; Eli Lilly historical commercial launch timelines for tirzepatide (Mounjaro, Zepbound). Estimated window subject to clinical and regulatory contingencies.
Disclaimer. Estimated dates are projections based on Eli Lilly public statements, ClinicalTrials.gov registry data (NCT05882045), and historical FDA review patterns. Not guarantees. Subject to clinical results and regulatory review timeline. Retatrutide is investigational and NOT FDA-approved. Not medical advice.
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Updated by our editorial team. Disclaimer: each entry below cites its primary source.
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Placeholder slot 1 — most recent Lilly disclosure or FDA action
Editorial team will fill this slot with the most recent verifiable Eli Lilly press release, SEC filing, or FDA docket entry. Each entry will include date, source link, and a 2-sentence plain-English summary.
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Placeholder slot 2 — second most recent verifiable update
Reserved for the next confirmed milestone (Phase 3 readout, NDA filing, FDA correspondence). Each entry must cite ClinicalTrials.gov, an Eli Lilly investor relations page, or the FDA orange book / docket.
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Placeholder slot 3 — third most recent verifiable update
Reserved for older but still relevant disclosures (peer-reviewed publication of a TRIUMPH trial, conference presentation at ADA/EASD/ObesityWeek). Editorial team will only publish content with a verifiable primary source.
Disclaimer: any update appearing here is a summary of public information. Retatrutide remains investigational and NOT FDA-approved. Not medical advice. Consult your physician.
No. As of 2026, Retatrutide (Eli Lilly LY3437943) is investigational. It is in Phase 3 clinical trials under the TRIUMPH program. It has not been submitted to the FDA for approval and is NOT available outside Eli Lilly's clinical trials.
Estimated FDA approval window is 2027–2028, contingent on full Phase 3 results, NDA submission timing, and FDA review. Eli Lilly is expected to submit the NDA in late 2026 or early 2027. These dates are projections and not guarantees.
Eli Lilly reported approximately 28.7% mean weight loss at the highest dose at 76 weeks in TRIUMPH-4 — the highest figure ever reported in a Phase 3 obesity trial. Full peer-reviewed publication is pending.
No. Compounded Retatrutide is NOT a legal pathway. Only semaglutide and tirzepatide are currently available as legally compounded preparations through licensed 503A pharmacies during recognized FDA shortages. Any product sold today as "retatrutide" is from unregulated sources and represents a serious safety risk. See our 2026 telehealth comparison for legal options today.
Sources
Not medical advice. This page is educational. Retatrutide is investigational and NOT FDA-approved as of 2026. Consult your physician before starting any GLP-1 medication. See our full FTC disclosure.