TRANSCEND-T2D-2: What Lilly's Retatrutide vs Ozempic Head-to-Head Readout Reports

What Did Lilly Announce on 28 October 2026?

On 28 October 2026 Eli Lilly and Company announced topline results from TRANSCEND-T2D-2, a Phase 3 head-to-head trial of retatrutide, its investigational GIP/GLP-1/glucagon triple receptor agonist, against injectable Ozempic (semaglutide) 2 mg in adults with type 2 diabetes.[1] Lilly described it as the sixth Phase 3 trial in which retatrutide met its objectives, and the first comparison against an established GLP-1 comparator in this programme.[1][2]

The headline figure was glycated haemoglobin (A1C) at 80 weeks: Lilly reported an average reduction of 2.2% on both the 9 mg and 12 mg retatrutide doses versus 1.8% on Ozempic.[1][3] Lilly also reported greater body-weight reductions than the comparator as a secondary outcome; we do not reproduce those figures here because this guide concerns trial design, evidence status and regulation, and the primary release should be consulted directly.[1]

Velox Peptides supplies retatrutide as an HPLC-verified (≥99% purity) lyophilised reagent for in vitro research use only. View the product page →

How Is a Head-to-Head Trial Different From Earlier Retatrutide Readouts?

Earlier readouts in the programme, including TRIUMPH-1, TRIUMPH-2 and TRIUMPH-3, compared retatrutide with placebo. Placebo-controlled designs establish that a drug differs from no active treatment; an active-comparator design asks a different question, namely how an investigational agent performs against an already-licensed one under the same protocol.[1] For regulators, payers and journal reviewers, the active comparator is the more demanding test, which is why the result drew wide industry coverage.[4]

TRANSCEND-T2D-2 sits in the TRANSCEND sub-programme, which enrols adults with type 2 diabetes, alongside the earlier TRANSCEND-T2D-1 results. Our existing retatrutide vs Ozempic comparison covers the pharmacology of the two molecules; this guide covers only what the new topline release does and does not establish.

What Did the Topline Report on Tolerability?

Press coverage of the release reported gastrointestinal adverse events as the most common, with diarrhoea in 28.3% of participants on retatrutide 9 mg and 32.7% on 12 mg, compared with 26.4% on Ozempic.[3] Treatment discontinuation due to adverse events was reported as 7.9% on the 12 mg dose.[3] Comparator-arm discontinuation and serious adverse event rates should be read from the primary release rather than from secondary summaries.

These are company-reported topline percentages, not peer-reviewed analyses. Earlier retatrutide trials have shown that tolerability findings often shift in meaning once full data, dose-escalation schedules and adjudicated safety tables are published, as seen in the TRIUMPH-2 Lancet safety paper.

What Is Still Unpublished, and What Is the Regulatory Position?

At the time of writing, TRANSCEND-T2D-2 exists only as a company announcement and press coverage. No peer-reviewed publication, conference presentation or full clinicaltrials.gov results record has been identified by us, and the trial's secondary endpoints, subgroup analyses and statistical methods are not independently verifiable.[1]

Retatrutide has not been approved by the FDA or any other regulator, and Lilly has said it plans to submit for US approval in early 2027.[3] See our guides on the CMC-driven filing timeline and the FDA and MHRA approval timeline. In the UK, no retatrutide medicine is licensed by the MHRA; licensed development by a pharmaceutical sponsor is a separate matter from the supply of laboratory reagents.

What Are the Limitations Researchers Should Note?

First, topline figures are selected by the sponsor and unreviewed; the primary-endpoint estimate, its confidence interval and the handling of missing data are not yet public. Second, a difference in A1C reduction between two agents at different dose levels does not by itself establish superiority in any broader sense, and the trial's pre-specified hierarchy of testing will determine which comparisons are formally interpretable. Third, the comparator was a single semaglutide dose in one population; results do not generalise to other populations or comparators. Fourth, the trial concerns Lilly's pharmaceutical product, and none of its findings describe the properties, purity or behaviour of any research-grade material.

Nothing here constitutes evidence of any therapeutic effect in humans beyond what the sponsor has formally reported, and Velox Peptides makes no therapeutic, weight-loss or efficacy claims for retatrutide or any compound named. Velox Peptides' retatrutide is supplied strictly for in vitro laboratory use.

Velox Peptides Supply Information

Retatrutide is supplied as a research reagent only. It is not a medicine and has not been evaluated by the MHRA or FDA. Not for human or veterinary use. See our Research Use Policy and MHRA Statement.

Frequently Asked Questions