No one has a date, and anyone who gives you one is projecting. What's confirmed: Lilly plans to submit retatrutide to the FDA in Q1 2027 — a timeline that moved from "by end of 2026" so the company could finish the manufacturing and quality (CMC) package. [1] Approval and launch come after review.
Realistic scenarios
Every row below is a projection built from the confirmed Q1 2027 submission plan — none of it is a commitment from Lilly or the FDA.
| Scenario | What it assumes | Possible U.S. availability |
|---|---|---|
| ProjectedStandard review | Submission in Q1 2027; a standard review commonly runs about 10 months | ~Late 2027 to early 2028 |
| ProjectedAccelerated review | A priority pathway is used — Lilly's own orforglipron (Foundayo) was approved 54 days after filing under a National Priority Voucher [3] | Months, not quarters, after submission |
| ProjectedDelayed | The CMC package or the BLA-vs-NDA classification dispute (in litigation since Sept 2024 [2]) pushes the submission or lengthens review | 2028 or later |
Launch logistics matter too: for high-demand metabolic drugs, manufacturing scale-up has sometimes constrained early supply.
What could move the timeline
- Faster: a priority review pathway. The Foundayo precedent shows Lilly can move from filing to approval in under two months when a voucher applies. [3]
- Slower: the application-type dispute. Lilly plans a BLA (biologic); the FDA classifies retatrutide as a drug requiring an NDA — litigation has run since September 2024. Under an NDA, market exclusivity would be 5 years. [2]
What you can do now
If your goal is treatment rather than one specific molecule, FDA-approved options (semaglutide, tirzepatide) exist today through medical weight-management practices — the RetaMaps directory shows what each practice currently advertises. If your goal is retatrutide specifically, the only legitimate routes are clinical trials and Lilly's expanded access program, where your physician applies on your behalf and medical criteria must be met. [5] [4] Establishing care with an obesity-medicine practice now also puts you in a better position if and when a new medication launches.
The moment anything on this timeline actually changes, the FDA approval tracker changes with it — and update list members get an email.