What comes after retatrutide? UBT251 and the next triple agonists

What happened

Since Eli Lilly sued six retatrutide sellers in August, a newer compound, UBT251, has started turning up in our vendor data. It's a once-weekly injected peptide that acts on the same three hormone receptors as retatrutide (GLP-1, GIP and glucagon), which is why both get called triple agonists. Our own tracking doesn't show retatrutide leaving vendor sites, and there's more on that below.

The United Laboratories in Hong Kong discovered it, and in March 2025 Novo Nordisk, the company behind Ozempic and Wegovy, paid $200 million upfront for the rights everywhere outside greater China. [4] Novo announced the headline obesity result in February, and in October the full results of two 24-week studies from China came out in a medical journal, one in adults with overweight or obesity and one in adults with type 2 diabetes. [3] [1] [2]

How much weight people lost on UBT251

The obesity trial enrolled 205 adults in China, average age 34 and average starting weight about 203 pounds. Everyone took a weekly injection for 24 weeks, stepping up over the first two to three months to a trial dose of 2, 4 or 6 milligrams, or placebo. [1]

At 24 weeks, average weight loss ran from 13.6% at the lowest dose to 19.7% on one of the two 4 mg schedules, against 2.0% on placebo. The top dose, 6 mg, landed at 18.7%, so more wasn't clearly better, and weight was still coming down when the trial ended. Waist, blood pressure, blood sugar and cholesterol improved too. [1]

Side effects were the familiar gut ones, led by diarrhea in about a third of people (10% on placebo), mostly mild to moderate and easing over time. One person out of 155 on UBT251 stopped because of side effects. Heart rate rose with dose, by about 10 beats a minute at 6 mg, and settled back near where it started four weeks after the last injection. [1]

In the diabetes trial of 211 adults, UBT251 lowered HbA1c, the three-month blood sugar average, by 2.0 to 2.2 points, against 1.8 on semaglutide 1 mg. Weight fell 8 to 10% against about 5%. Every dose beat semaglutide on weight, but on blood sugar only the lowest dose pulled clearly ahead. [2]

How it lines up against retatrutide

Week 24 is the fairest match, since both drugs' mid-stage trials measured it. UBT251's obesity trial was younger Chinese adults starting around 203 pounds, and retatrutide's was U.S. adults starting around 237 pounds, about half of them men, so the rows are context, not a scoreboard. [1] [6]

Retatrutide went on to 24.2% at 48 weeks [6], and its main late-stage obesity trial reached 28.3% at 80 weeks on the top dose in Lilly's headline analysis, and 30.3% at two years for people starting with a BMI of 35 or more who stayed on into an extension. [7] Its six-day half-life comes from an early trial. [12] For UBT251, neither the half-life nor how strongly it acts on each receptor has been published, so any number you see for those didn't come from a paper. If the heart-rate row sounds familiar, here's why your heart races on retatrutide.

Who else is after retatrutide

UBT251 isn't the only triple agonist in line. Three others with trials on the record:

• Zantrutide from Hanmi in Korea is being tested for obesity and for type 2 diabetes, with no results yet. [8] [13]
• HRS-4729 from Hengrui, licensed to Kailera Therapeutics outside China, has a mid-stage obesity trial registered in China. [14] In a 12-week early trial, the 10 people on the top dose averaged up to 16% weight loss. [9]
• Efocipegtrutide, also from Hanmi, finished a trial in fatty liver disease rather than weight in July, and the results aren't out. [10]

What this means for you right now

If you're on retatrutide, our data doesn't show it leaving. Since the August lawsuits, nothing in our daily tracking shows a published vendor taking retatrutide off sale, and 41 vendors we track list it today. That number has grown since summer mostly because we've added vendors, so read it as still widely available, not more popular. If your own vendor pulled it, here's what that usually means.

UBT251 is a different picture. It's only just turning up in our data, listed separately from retatrutide, and as of November 9 it was out of stock. Watch the names, too, because "GLP-3" on a vendor page is the usual code name for retatrutide, not UBT251. Whichever you're weighing, read the certificate of analysis through our vendor directory and compare per-milligram prices at app.peptidepricelab.com before ordering from someone new.

What to watch next

Novo's global trial of about 330 people is due to report in 2027, the first UBT251 data from outside China. [3] A year-long late-stage trial in 600 adults with overweight or obesity started dosing in China in September. [5] Lilly plans to file retatrutide with the FDA in early 2027. [11] We'll cover each as it lands.