TRIUMPH-2 and -3 results; Lilly to file with FDA in 2027

On 23 July 2026 Lilly announced positive topline results from two more Phase 3 trials, TRIUMPH-2 in people with type 2 diabetes and TRIUMPH-3 in people with severe obesity and heart disease, and said it plans to file for US approval in the first quarter of 2027.^[1][2] Over the following weeks the gap between that timetable and the black market became the bigger story.

What was announced

TRIUMPH-2 answered a question the earlier trials could not: does retatrutide work as well in people with type 2 diabetes, who usually lose less weight on this class of drug? Weight loss was lower than in TRIUMPH-1, at 12.7%, 19.1% and 20.8% versus 4.0% on placebo, but still large. Blood sugar control improved by 1.4 to 1.6 points of HbA1c from a starting average of 7.7%, against 0.2 points on placebo. Stopping because of side effects ran at 3.8%, 11.6% and 7.7% versus 4.9%.^[1]

TRIUMPH-3 enrolled people with severe obesity who already had cardiovascular disease, with or without diabetes. The two doses tested produced 21.6% and 22.6% average loss against 3.2% on placebo. Drop-outs for side effects were 9.8% and 13.5% versus 4.8%. The trial was not designed to measure heart attacks or strokes; that is the job of the 10,000-person TRIUMPH-Outcomes study, due around 2029.^[1][5]

All of these are efficacy-estimand figures, which count people while they stayed on the drug. The more conservative treatment-regimen figures will come with the papers. See how to read a trial, and the TRIUMPH-2 and TRIUMPH-3 pages.

What the filing plan means for the UK

A Q1 2027 US application means an FDA decision no earlier than late 2027 or 2028 if the review takes a typical year. Lilly has given no date for the UK. The MHRA runs its own separate review. After authorisation, NHS access needs a NICE appraisal and a rollout plan, which for the existing weight-loss injections has taken years.

Our editorial estimate, and it is only that: MHRA authorisation no earlier than 2027 to 2028, and NHS availability later still. Any site giving a firm UK date is guessing. The legal position until then is unchanged: retatrutide cannot lawfully be sold or supplied for people to use in the UK. See is it legal in the UK?

August: lawsuits and listings

On 12 August Lilly filed six lawsuits in the US against businesses it says are selling retatrutide illegally, and said it had made more than 200 referrals to the FDA, the Department of Justice and state attorneys general. It reported finding more than 14,000 websites, adverts, posts and listings offering retatrutide in more than 100 countries. The FDA had said in June that selling retatrutide to consumers is illegal and that it cannot lawfully be compounded.^[6][3] We do not name the defendants; this site does not identify sellers.

28 August: one in eighteen

ABC News reported new laboratory results from an Australian analytical company on 18 samples sold as retatrutide during 2026. Only one matched its label. Some were around 30% stronger than stated, some around 30% weaker, and one contained no retatrutide at all. The peptide typically made up about a tenth of what was in the vial; the rest was unaccounted for.^[4] The testing page collects every published analysis.

What it does not mean

• Positive trials do not make the drug available. Filing is a plan, not an approval.
• Efficacy-estimand figures are the drug's best case. The everyone-randomised figures will be lower.
• A lawsuit in the US changes nothing about what is in a vial in the UK.