What is retatrutide? Early tests suggest it may be the strongest GLP-1 yet

by [Meaghan Cameron](/content/author/eu4pr7pm5o/ "Posts by Meaghan Cameron"/index.html)

What you’ll learn:

• Retatrutide is a medication that is being tested for weight loss and is still in clinical trials.
• It works by targeting three pathways as opposed to one for semaglutide and two for tirzepatide, creating a powerful effect on appetite and blood sugar regulation.
• In early studies, people taking retatrutide lost as much as 24% of their body weight in less than a year.
• Retatrutide’s trials are expected to run until at least 2026, and it isn’t available yet outside of research studies.

If you’ve been following the rise of GLP-1 medications like semaglutide, you know they’ve reshaped the way many people approach weight loss. These treatments work by mimicking hormones to help regulate appetite, slow digestion, and balance blood sugar. But there are several medications being tested that developers think could be even more powerful.

Retatrutide is a medication still in clinical trials that might surpass these popular medications in weight-loss effectiveness. Eli Lilly, the company behind Mounjaro® and Zepbound®, is leading the development of this new injectable medication.

Retatrutide is being studied as the first weight-loss drug to target three different pathways at once: GLP-1, GIP, and glucagon. This new approach could mean bigger changes for weight management than what we’ve seen so far. And while it’s not yet available, many experts are already calling it one to watch.

What is retatrutide?

Retatrutide is an injectable medication currently being studied for both weight management and type 2 diabetes.

How is retatrutide taken?

Like GLP-1 medications, retatrutide is taken as a once-a-week injection. Clinical trials followed a step-up dosing schedule, starting low and moving up gradually. People were tested on these weekly doses:

• 1 milligram (mg)
• 4 mg (starting at either 2 mg or 4 mg)
• 8 mg (starting at either 2 mg or 4 mg)
• 12 mg (starting at 2 mg)

The highest dose tested was 12 mg per week, and the gradual increase was important for making side effects easier to handle.

How much weight can you lose with retatrutide?

Early research suggests retatrutide may be one of the most powerful weight-loss medications studied so far. In a 48-week clinical trial, people taking the highest dose (12 mg weekly) lost an average of 24% of their body weight. For someone starting at 240 pounds, that’s about 58 pounds.

Even at lower doses, the results were impressive—people taking 8 mg lost around 17% of their body weight in 24 weeks. People with type 2 diabetes also saw meaningful weight loss in early studies, along with better blood sugar control.

These findings suggest retatrutide could set a new bar in weight-loss treatment, potentially even more effective than today’s top GLP-1 options.

What does retatrutide cost?

Since retatrutide is still in trials, there’s no official price tag (or even brand name) yet. Looking at comparable GLP-1 medications can give us a ballpark idea:

• Wegovy® (semaglutide) pens have a list price of about $1,350 per month without insurance.
• The Zepbound® (tirzepatide) pens have a list price of around $1,000 without insurance.

Retatrutide: Side effects and safety considerations

As promising as retatrutide looks for weight management, it’s important to know about possible side effects. Trials suggest its side effect profile looks a lot like what’s been seen with other GLP-1 drugs like Wegovy® and Zepbound®. These issues are typically related to the digestive system and tend to show up when the dose is increased.

The most common side effects that showed up in trials include:

• Nausea, vomiting, or diarrhea
• Constipation
• Fatigue or tiredness

Most of these effects were mild to moderate and tended to improve as the body adjusted. Still, some people found the side effects difficult enough to stop treatment— 6% to 16% of participants discontinued retatrutide.

Retatrutide: Clinical trials and FDA status

Retatrutide has now reached phase 3 trials, which is one of the biggest steps before a new drug can be submitted to the Food and Drug Administration (FDA).

If the results continue to look strong, Eli Lilly could seek FDA approval as early as 2026. For now, though, it’s still experimental and only available to people taking part in clinical studies.

Retatrutide vs. other weight-loss drugs

Retatrutide is still in clinical trials, but the results so far have been very promising. Studies have shown that people taking the highest dose lost nearly a quarter of their body weight over about a year. That’s more than what’s typically seen with today’s leading GLP-1s.

To put things in perspective, here’s how retatrutide’s trial data compares to Zepbound® and Wegovy®:

Is it true that there are counterfeit versions of retatrutide?

Unfortunately, yes. Even though retatrutide isn’t FDA-approved yet and is still only available in clinical studies, counterfeit versions are already being advertised and sold online.

The FDA has issued warnings about this exact issue, cautioning people not to purchase unapproved drugs labeled “for research only” or “not for human consumption.”

Until retatrutide is officially FDA-approved and available at pharmacies, the safest choice is to avoid anything that claims to be it.

Frequently asked questions about retatrutide

When will retatrutide be available?

Retatrutide is still in phase 3 trials, so it’s not on the market yet. If everything goes well, approval could happen as soon as 2026. Until then, the only way to access it is by joining a clinical trial, which has specific eligibility requirements.

Is retatrutide more effective than Zepbound® or Wegovy®?

Early studies suggest retatrutide may lead to more weight loss than current options, with people losing around 24% of their body weight compared to about 21% with Zepbound® and 15% with Wegovy®. More direct head-to-head studies will be needed to confirm how it really stacks up against other weight-loss medications.

How does targeting the glucagon receptor make retatrutide different?

Current GLP-1 drugs work on one or two pathways, but retatrutide adds a third by targeting the glucagon receptor. Combined with the appetite and blood sugar effects of GLP-1 and GIP, the three together may create a stronger, synergistic effect that explains the impressive results seen in early trials.

What long-term safety data do we have for retatrutide?

Long-term data on retatrutide is still pretty limited. So far, the longest completed study has followed people for about 48 weeks. The good news is that the phase 3 trials are set to run much longer—up to about two years—so we’ll have a clearer picture of safety and results once those wrap up.

Could retatrutide be used for conditions beyond weight loss and diabetes?

Right now, there’s no definite answer on whether retatrutide could be used for conditions other than weight management and diabetes. Some early research is looking into its potential for fatty liver disease, sleep apnea, and even heart and kidney health. But it’s too soon to say how effective it might be, and any new uses would require separate FDA approval once the studies are complete.

The bottom line: Retatrutide might be a powerful weight-loss choice in a few years

Retatrutide is shaping up to be one of the most exciting developments in weight management, with early trials showing average weight loss of around 24% over 48 weeks. That’s more than what we’ve seen with today’s leading medications.

In the meantime, there are safe, effective treatments already on the market—and they work best when combined with changes that support your everyday habits. If you’re curious about GLP-1s or other weight-loss drugs, see if you qualify for Noom Med. If you qualify, you’ll be connected with a qualified clinician who can find the right medication for you and prescribe it if needed.