In the first late-stage trial to test retatrutide head-to-head against Ozempic (semaglutide), retatrutide lowered A1C by 2.2 points on average over 80 weeks, and Ozempic lowered it by 1.8 points. People on retatrutide also lost more than twice as much weight. Eli Lilly, which makes retatrutide, announced the results today, 28 October 2026: Lilly's retatrutide delivered greater A1C reduction and more than double the weight loss of Ozempic's highest approved dose in head-to-head trial.
What A1C is
A1C is a blood test that shows your average blood sugar over about the last 3 months, as a percentage. Under 5.7% is normal, 5.7% to 6.4% is prediabetes, and 6.5% or higher is diabetes. For most people with diabetes, the goal is 7% or less. Those ranges are from the CDC's A1C Test for Diabetes and Prediabetes.
A1C is already a percentage, so going from 8.3% to 6.1% is a drop of 2.2 points. Lilly writes that as "2.2%". Same thing.
The A1C results
- People started at an A1C of 8.3% on average.
- Retatrutide brought it down 2.2 points, to about 6.1%. Both doses tested, 9 mg and 12 mg, got the same 2.2.
- Ozempic brought it down 1.8 points, to about 6.5%.
- So on average, both drugs got people under the 7% goal. Retatrutide went 0.4 points further.
Who was in the trial
- 1,298 adults with type 2 diabetes whose blood sugar was still too high on metformin, a common diabetes pill. Some also took an SGLT2 inhibitor, another kind of diabetes pill.
- Each person got one shot a week: retatrutide 9 mg, retatrutide 12 mg or Ozempic 2 mg. 2 mg is the highest dose on Ozempic's FDA label, OZEMPIC (semaglutide) injection — Prescribing Information.
- It lasted 80 weeks, about a year and a half.
Weight
- Retatrutide 9 mg: 19.5% of body weight, about 44 lb (20 kg).
- Retatrutide 12 mg: 20.9%, about 47 lb (21.5 kg).
- Ozempic 2 mg: 9.4%, about 21 lb (9.5 kg).
- People started at about 226 lb (102 kg). Lilly says retatrutide also improved non-HDL cholesterol (the "bad" kinds), triglycerides (a blood fat) and systolic blood pressure (the top number) more than Ozempic, but it hasn't published those figures yet.
Side effects
- Stomach side effects were common in every group. Diarrhea: 26% on Ozempic, 28–33% on retatrutide. Nausea: 21–24% in every group. Vomiting: 10–15% across the groups. Constipation was more common on Ozempic: 20%, against 13–14% on retatrutide.
- More people stopped retatrutide because of side effects: 4.8% on 9 mg and 7.9% on 12 mg, against 2.7% on Ozempic.
- Dysesthesia, an odd skin feeling such as tingling, burning or skin that's sore to the touch, was more common on retatrutide: 4.8% and 6.5%, against 2.7% on Ozempic.
- Lilly says most side effects were mild to moderate and usually went away during treatment.
The fine print
- These are Lilly's first headline numbers, from its own announcement. The full results haven't been published or checked by outside scientists yet; Lilly says they will be presented at a medical meeting and published in a journal.
- Lilly ran the trial. Ozempic is made by its rival, Novo Nordisk.
- Lilly's numbers assume everyone stayed on their drug for all 80 weeks. Numbers that also count people who stopped early are often a bit smaller, and Lilly hasn't released those yet.
- Everyone knew which drug they were getting. The trial wasn't blinded.
- The trial was set up mainly to show that retatrutide 12 mg is at least as good as Ozempic at lowering A1C. It was, and it did better. The 9 mg dose had the same 2.2-point drop, but in the trial's statistics that counts as a supporting result, not the main one.
- Retatrutide isn't approved anywhere as of 28 October 2026. Lilly says it plans to apply for FDA approval in the first quarter of 2027. Ozempic is FDA-approved for adults with type 2 diabetes.
Questions?
Post them below. If you track your own A1C and want to share it, use the template in the forum rules so others can match it to a tested batch. Staff don't give doses or medical advice.