Retatrutide vs. Ozempic in 2026: The First Head-to-Head Trial Shows More Than Double the Weight Loss

On October 28, 2026, Eli Lilly announced topline results from TRANSCEND-T2D-2, a Phase 3 trial of 1,298 adults with type 2 diabetes that wasn't adequately controlled on metformin (with or without an SGLT2 inhibitor). Participants were randomized to one of three weekly injections: retatrutide 9 mg, retatrutide 12 mg, or semaglutide 2 mg — the highest dose of Ozempic approved for type 2 diabetes.

It's the first Phase 3 trial to compare retatrutide head-to-head with another incretin therapy, and Lilly's sixth positive Phase 3 readout for the drug.

After 80 weeks, according to the trial results:

• Both retatrutide doses lowered A1C by 2.2 percentage points, versus 1.8 points with semaglutide, from an average starting A1C of 8.3%.
• Retatrutide 12 mg produced 20.9% average weight loss (about 47 lbs); the 9 mg dose produced 19.5% (about 44 lbs).
• Semaglutide 2 mg produced 9.4% average weight loss (about 21 lbs).

Participants started the trial at an average weight of 225.8 lbs with a BMI of 36.8, so these are people living with both diabetes and significant excess weight — a very common combination.

Retatrutide is often called the "triple G" because it targets three hormone receptors — GLP-1, GIP, and glucagon — while Ozempic and Wegovy (semaglutide) target only GLP-1, and Zepbound (tirzepatide) targets two. The theory has been that hitting three pathways produces more weight loss, and this trial is the strongest direct evidence yet.

Weight loss in the 20% range from a medication is territory that, until recently, only bariatric surgery reliably reached. For people with type 2 diabetes — who historically lose less weight on these drugs than people without diabetes — a 20.9% average result is remarkable. As analysts noted, the 12 mg dose was statistically superior to semaglutide on both A1C and weight loss.

One important caveat: this was an open-label trial (participants knew which drug they were taking), and these are company-reported topline numbers that haven't yet been through peer review. Full results are expected at a medical meeting and in a journal publication later.

Retatrutide's side effect profile looked broadly similar to other incretin drugs, with gastrointestinal symptoms leading the list. Diarrhea affected 28–33% of retatrutide patients versus 26% on semaglutide, and nausea affected 21–24% versus 21%. Vomiting at the 12 mg dose (15%) was slightly higher than semaglutide (13.2%). Interestingly, constipation was less common with retatrutide.

Two numbers worth watching: dysesthesia (unusual skin sensations like tingling or burning) occurred in up to 6.5% of retatrutide patients versus 2.7% on semaglutide, and dropout due to side effects was higher at the 12 mg dose (7.9% vs. 2.7%). Most adverse events were mild to moderate and resolved during treatment, per Lilly.

As with any GLP-1-class medication, these drugs aren't right for everyone — people with a personal or family history of medullary thyroid carcinoma or MEN 2, or a history of pancreatitis, are typically screened out, which is why a licensed provider should always review your health history first. If nausea is what worries you, there are also prescription anti-nausea options that providers commonly pair with GLP-1 therapy.

Retatrutide is still investigational. It is not approved by the FDA for any use, no approval date is guaranteed, and Lilly has not announced a submission timeline alongside these results. Realistically, you cannot get legitimate retatrutide today outside a clinical trial.

That gap between hype and availability has fueled a dangerous gray market. As we covered recently, thousands of people are already buying unapproved "reta" online, and the FDA has received reports of serious harm, including deaths, linked to black-market versions. No trial result — however impressive — makes an unregulated vial from an overseas website safe. If you see "retatrutide" for sale right now, it is not the drug from this trial.

The good news: the medications retatrutide was tested against — and their close relatives — are FDA-approved, well studied, and available today.

• Semaglutide (Ozempic, Wegovy) still delivered a 1.8-point A1C drop and ~9% weight loss in this very trial — meaningful, proven results.
• Tirzepatide (Mounjaro, Zepbound), the dual-agonist, has produced around 20% average weight loss in its own obesity trials, and JoeyMed offers high-dose tirzepatide programs for eligible patients.
• Lifestyle support, dose titration, and side effect management make a real difference in how much weight patients actually lose and keep off.

If retatrutide is eventually approved, patients already established in a medically supervised weight loss program will be well positioned to discuss switching with their provider. Until then, the best move is starting with what's proven — not waiting years for what's next, and definitely not risking black-market peptides.

If you have type 2 diabetes or excess weight and want to know which of today's options fits your health profile, JoeyMed can help. Our licensed providers review your medical history, screen for contraindications, and prescribe FDA-approved or legitimately compounded treatments when appropriate — all through a straightforward online visit, with medications shipped to your door and ongoing support for dosing and side effects.

Explore our weight loss treatment options or browse our wellness programs to get started today. Treatment decisions are always made with a licensed provider, based on your individual health — because the right medication is the one that's right for you.