Retatrutide has quickly become one of the most closely watched medications in obesity research—and it's now moving closer to FDA review.

Eli Lilly has reported positive results from five Phase 3 clinical trials involving retatrutide. The company says it now has the clinical data package needed to support global regulatory submissions for obesity, knee osteoarthritis pain and obstructive sleep apnea.

Lilly currently plans to submit retatrutide to the U.S. FDA in the first quarter of 2027.

But there's an important distinction: retatrutide is not FDA approved today, and an FDA submission does not guarantee approval.

What Is Retatrutide?

Retatrutide is an investigational medication being developed by Eli Lilly. It's a once-weekly injectable triple hormone receptor agonist targeting three pathways:

GIP + GLP-1 + glucagon

That third glucagon pathway distinguishes retatrutide from medications such as tirzepatide, which targets GIP and GLP-1 receptors.

You may also see retatrutide called a “GLP-3” online, but Lilly notes that this isn't a scientifically accurate term. Triple agonist is the more appropriate description.

What Did the Phase 3 Trials Show?

The results have generated considerable attention.

In the Phase 3 TRIUMPH-1 trial, adults with obesity or overweight without diabetes receiving the 12 mg dose lost an average of 28.3% of their body weight—or 70.3 pounds—at 80 weeks.

Among participants with a starting BMI of 35 or greater who continued into an extension, average weight loss reached 30.3% at 104 weeks.

Retatrutide has also produced positive results in populations with type 2 diabetes and cardiovascular disease.

In TRIUMPH-2, participants with obesity or overweight and type 2 diabetes lost up to an average of 20.8% of their body weight.

In TRIUMPH-3, participants with severe obesity and established cardiovascular disease lost up to an average of 22.6%.

Researchers are also studying retatrutide for several obesity-related conditions, including obstructive sleep apnea and knee osteoarthritis pain.

When Will Retatrutide Be Submitted to the FDA?

This is where the story has recently changed.

Lilly says it now has the clinical data package needed to support global regulatory submissions for retatrutide as a potential treatment for obesity, knee osteoarthritis pain and obstructive sleep apnea.

The company plans to submit its application to the FDA in Q1 2027.

That represents an important step toward potentially bringing retatrutide to patients.

When Could Retatrutide Be FDA Approved?

We don't know yet.

Submitting an application begins the FDA review process—it isn't an approval.

The FDA must review the evidence supporting the medication's safety, effectiveness, manufacturing and proposed labeling before deciding whether to approve it.

Therefore, claims that retatrutide has a confirmed “release date” are premature.

For now, the most accurate timeline is:

Phase 3 results → planned FDA submission in Q1 2027 → FDA review → potential regulatory decision

The timing and outcome of that review will ultimately be determined by the FDA.

Can You Get Retatrutide Now?

Not legally as an approved prescription medication.

Retatrutide remains investigational and has not been approved by the FDA or another regulatory agency.

Lilly says it is legally available only to participants in its clinical trials and specifically warns consumers against products being sold online or through other channels claiming to contain retatrutide.

This is particularly important because interest in retatrutide has grown well ahead of regulatory approval.

Products advertised as “research-grade retatrutide” or otherwise sold directly to consumers should not be confused with the medication being evaluated in Lilly's controlled clinical trials.

What Happens Next?

Retatrutide still has several regulatory steps ahead, but 2026 has significantly changed what we know about the drug.

We now have results from multiple Phase 3 trials, including substantial average weight loss in several patient populations, and Lilly has publicly identified Q1 2027 as its planned FDA submission window.

Additional retatrutide studies are also continuing in areas including type 2 diabetes, cardiovascular and kidney outcomes, chronic low back pain and metabolic dysfunction-associated steatotic liver disease.

For now, the most important takeaway is simple:

Retatrutide is getting closer to FDA review—but it is still an investigational medication, not an FDA-approved treatment.

As the regulatory process progresses, we'll continue following the evidence and FDA developments.