Verified timeline

Retatrutide approval timeline

Every dated milestone, with the source that establishes it. Events that have not happened are drawn differently from events that have — because the difference is the whole point.

By Evan Marsh · Updated

There is no retatrutide FDA approval timeline, because no application has been filed. The record runs from the first human study in 2019 to five positive Phase 3 readouts disclosed between December 2025 and July 2026. The only dated step ahead is Lilly's stated plan to submit a Biologics License Application in Q1 2027 — a company projection, not an FDA schedule.

9events on the record
4steps not yet taken
0FDA decisions made

Next expected milestone

Planned regulatory submission window

Lilly’s stated Q1 2027 filing window opensJanuary 1, 2027

This tracks a stated filing window, not an FDA approval date.

Window
Q1 2027
Set by
Eli Lilly, not the FDA
Is this an approval date?
No

Lilly has publicly stated a planned submission window. A submission is the start of FDA review, not an approval, and the window is the company's own projection rather than a date set by the FDA.

“Lilly is completing the comprehensive Chemistry, Manufacturing, and Controls (CMC) data package required for a Biologics License Application (BLA) and plans to subsequently submit retatrutide in Q1 2027 for U.S. approval.”

Eli Lilly and Company, July 23, 2026

What has not happened yetNot yet occurred

  1. Q1 2027

    Planned BLA submission to the FDA

    The window Lilly has stated for filing a Biologics License Application. This is the company's own projection. It has not happened, and the FDA has not set or endorsed this date.

    Lilly's triple agonist retatrutide successful in two additional Phase 3 obesity trials · Eli Lilly and Company

  2. No date set

    FDA decides whether to accept the application

    After a submission, the FDA has roughly 60 days to decide whether the application is complete enough to review. Acceptance is not approval — it means the review clock starts and a decision date is assigned.

    Drugs@FDA: FDA-Approved Drugs · U.S. Food and Drug Administration

  3. No date set

    FDA decision date (PDUFA date) set

    The target date by which the FDA aims to complete its review. No such date exists for retatrutide, and none can exist before an application is filed and accepted.

    Drugs@FDA: FDA-Approved Drugs · U.S. Food and Drug Administration

  4. No date set

    FDA decision: approval or complete response

    The review ends in either an approval or a Complete Response Letter setting out what would have to change. Neither outcome is guaranteed, and Lilly's own disclaimer states there is no guarantee that retatrutide will receive regulatory approval.

    Drugs@FDA: FDA-Approved Drugs · U.S. Food and Drug Administration

Verified recordOccurred

  1. Lilly states a Q1 2027 BLA submission plan

    In the same release, Lilly says it is completing the Chemistry, Manufacturing and Controls data package and “plans to subsequently submit retatrutide in Q1 2027 for U.S. approval.” Stating a plan is a corporate disclosure, not a regulatory step — nothing has been filed with the FDA.

    Lilly's triple agonist retatrutide successful in two additional Phase 3 obesity trials · Eli Lilly and Company

  2. TRIUMPH-2 and TRIUMPH-3 topline results

    Lilly reports positive topline results from two more pivotal Phase 3 trials, bringing the number of Phase 3 studies it describes as positive to five.

    Lilly's triple agonist retatrutide successful in two additional Phase 3 obesity trials · Eli Lilly and Company

  3. First Phase 3 peer-reviewed publication

    TRANSCEND-T2D-1 is published in The Lancet — as of the last verification date, the only Phase 3 retatrutide trial to have been through external peer review.

    Efficacy and safety of retatrutide in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1) · The Lancet

  4. TRIUMPH-1 topline results

    Lilly reports positive topline results from its pivotal Phase 3 obesity trial, including a pre-specified 104-week extension in participants with a BMI of 35 or above.

    Lilly's triple agonist retatrutide delivered powerful weight loss in pivotal Phase 3 obesity trial · Eli Lilly and Company

  5. TRANSCEND-T2D-1 topline results

    Lilly reports positive topline results in adults with type 2 diabetes inadequately controlled on diet and exercise alone.

    Lilly's triple agonist retatrutide demonstrated significant A1C and weight reductions in Phase 3 type 2 diabetes trial · Eli Lilly and Company

  6. First Phase 3 readout: TRIUMPH-4

    Lilly reports positive topline results from TRIUMPH-4, in adults with obesity or overweight and knee osteoarthritis. This is the first Phase 3 trial in the programme to read out.

    Lilly's triple agonist retatrutide delivered weight loss along with relief from osteoarthritis pain in first successful Phase 3 trial · Eli Lilly and Company

  7. Phase 2 obesity results published in the NEJM

    Peer-reviewed Phase 2 results in obesity appear in the New England Journal of Medicine, establishing the case for a Phase 3 programme.

    Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial · New England Journal of Medicine

  8. TRIUMPH-1 begins

    The pivotal Phase 3 obesity trial starts. It eventually randomises 2,335 participants and runs to 80 weeks with a pre-specified 104-week extension.

    ClinicalTrials.gov — retatrutide studies · U.S. National Library of Medicine · NCT05929066

  9. First-in-human study begins

    The first Phase 1 study of LY3437943 — the molecule now called retatrutide — starts dosing healthy participants.

    ClinicalTrials.gov — retatrutide studies · U.S. National Library of Medicine · NCT03841630

How to read this timeline

Filled markers are events that happened, on the date shown, established by the source linked beneath them. Hollow markers on a dashed line are steps in the regulatory process that have not occurred. Most of them have no date at all, because they depend on decisions the FDA has not made and cannot make until Lilly files.

The one dated future entry — the Q1 2027 submission window — is drawn the same hollow way as the undated ones, deliberately. A date attached to a plan is still a plan. Lilly could file in January 2027, in June 2027, or not at all.

What this timeline deliberately does not show

  • An approval date. None exists.
  • A PDUFA date. None can exist before a filing is accepted.
  • A launch date, a price, or a brand name.
  • Analyst forecasts or press speculation about when approval “should” arrive.
  • Rumoured filings. Only what a primary source establishes gets a marker.

If something here is wrong

Dates get misread and sources get updated. If an entry on this page is inaccurate,say so and it will be fixed and logged publicly at/corrections, with what was wrong and when it changed.

Questions

What is the retatrutide FDA approval timeline?

There is no approval timeline, because no application has been filed. The only dated future step is Lilly’s stated plan to submit a Biologics License Application in Q1 2027. Everything after that depends on FDA decisions that have not been made.

When will retatrutide be released?

No release or launch date exists. A launch would follow an approval, and there has been no submission, no review and no approval.