Approval Watch: When Will Retatrutide Be FDA Approved?

Retatrutide is not FDA-approved as of October 2026, but it's closer than ever. Eli Lilly now has five successful Phase 3 trials and says it plans to submit the drug to FDA by the end of the first quarter of 2027. A standard review takes about 10 to 12 months after filing, so a realistic decision window is late 2027 or 2028, unless FDA grants a faster review.

Until then, retatrutide is legally available only inside Lilly's clinical trials. Here's where the approval process stands, what's still missing, and what to watch next. If you're new to it, read what retatrutide is and how it works.

Most peptide drugs, like semaglutide, go through FDA's regular drug pathway (an NDA). Lilly is preparing a Biologics License Application for retatrutide, reflecting how FDA classifies the molecule. For patients the practical difference is small. It matters mainly for future copies: a biologic would face biosimilar rules rather than standard generic rules when patents expire.

Speed-ups: a priority review or a national priority voucher could shorten FDA's clock. Slow-downs: manufacturing questions, safety signals that need more study, or requests for additional data. Two open safety questions reviewers will look at closely are higher rates of nausea and vomiting at the top dose and dysesthesia, a skin-sensitivity effect seen in about 12% of people on 9 mg and 12 mg. In TRIUMPH-3, major cardiovascular events weren't significantly reduced, though there were few events. See our side-effects page.

TRIUMPH-5 compares retatrutide directly with tirzepatide, the drug in Zepbound and Mounjaro, without a placebo group. It runs to the end of 2026. It's the first trial that can say whether retatrutide actually beats the strongest approved option, rather than relying on cross-trial comparisons. See retatrutide vs Ozempic, Wegovy and Zepbound. Our retatrutide vs tirzepatide guide covers what we know until then.

Because the drug isn't approved, anything sold online as retatrutide, "GLP-3" or "reta" for research use is outside FDA oversight. FDA has warned about companies selling unapproved retatrutide and says it can't be compounded. There's no guarantee about what's in the vial, how much, or how clean it is. Legal access today means a clinical trial.

Wondering what it will cost once approved? Our guide to how much retatrutide will cost looks at Zepbound and Wegovy pricing in 2026 and what that suggests for a launch price.

Until approval, the only retatrutide outside trials is gray-market powder marketed as "GLP-3 RT." We explain why that label is misleading, and what FDA has done about the sellers, in what is GLP-3 RT.

Until FDA acts on the 2027 filing, enrolling in a TRIUMPH or follow-on study is the only legal way to take retatrutide. Our guide to how to get retatrutide covers eligibility, placebo odds and the approved alternatives meanwhile.

Retatrutide isn't approved, but its path is clear: five positive Phase 3 trials, a planned FDA filing by Q1 2027, and a likely decision in late 2027 or 2028. The head-to-head TRIUMPH-5 results and FDA's review of its side-effect profile are the two things most likely to shape when, and how, it reaches patients. For the full trial numbers, see retatrutide weight loss results.