Retatrutide + Cagrilintide

Where the name "Retatrutide + Cagrilintide" comes from

The name is community and market usage. Peptide Health Lab neither coined it nor endorses it, and this page exists because it is what people type into a search box rather than because it describes anything a laboratory has made.

Where it came from is not documented. A PubMed search on 1 September 2026 for retatrutide AND cagrilintide returned 18 records, and reading their titles and publication types shows what kind of documents they are: narrative reviews, systematic reviews, and pipeline surveys of obesity pharmacotherapy. Not one proposes the pairing, defines it, or reports administering the two together. Seventeen carry Review, Systematic Review or Network Meta-Analysis in PubMed's own publication-type field; the eighteenth is typed only Journal Article and is a narrative review of peptide-based therapies, which is a reminder that the absence of a Review tag is not evidence of a trial. This page therefore states the origin as undocumented on that dated search rather than inventing a provenance for it.

The most likely reason the name exists at all is a resemblance to something real. Two amylin-plus-incretin development programmes genuinely exist, and the largest published syntheses of obesity drugs describe both.^[1] Neither of them is this one.

What's in it and why people combine them

Retatrutide is not a GLP-1 receptor agonist. It is an agonist at three receptors — glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1, and glucagon — and reviews that file it under "GLP-1 receptor agonists and co-agonists" are using a convenient heading, not a mechanism. Its published human evidence is a 48-week phase 2 dose-finding trial in 338 adults with obesity, where least-squares mean weight change at 48 weeks ran from −8.7% in the lowest dose group to −24.2% in the highest, against −2.1% on placebo, with dose-related gastrointestinal events and a dose-dependent heart-rate rise that peaked at 24 weeks.^[2]

Cagrilintide is an amylin analogue, and by itself it is a much smaller number than its reputation. Its one dedicated single-agent efficacy trial randomized 706 adults over 26 weeks and reported mean weight reductions of 6.0% to 10.8% across the dose groups against 3.0% on placebo, with the highest group separating from liraglutide by 1.8 percentage points at p=0.03.^[3]

The reasoning behind putting them together is a mechanism story. Amylin signalling and incretin signalling are separate satiety pathways, so combining them sounds additive. That is a hypothesis about pharmacology. It is not a result, and this page does not treat it as one.

What the evidence says about the combination

Nothing has been published, and here is the search that establishes it. On 1 September 2026, PubMed returned 18 records for retatrutide AND cagrilintide; 18 for the synonym-expanded (retatrutide OR LY3437943) AND (cagrilintide OR AM833); 0 for LY3437943 AND AM833; 12 when the two names were combined with combination, combined, co-administration, co-administered and "administered together"; and 0 when the same two names were restricted with the randomized controlled trial and clinical trial publication-type filters. On the same day, the ClinicalTrials.gov API v2 returned a total count of 0 for both query.term=retatrutide AND cagrilintide and query.intr=retatrutide AND cagrilintide, and 0 for query.term=retatrutide AND amylin. Those are the queries, the databases and the date; anyone can re-run them.

A note on one synonym, because it will mislead anyone who tries. An unqualified PubMed search for AM833 on 1 September 2026 returned 680 records, while the title/abstract-restricted AM833[tiab] returned 23, most of them papers from the 1980s and 1990s with nothing to do with this molecule. A count from that synonym is not a finding unless every record was opened.

The evidence people reach for belongs to a different pairing. CagriSema is cagrilintide with semaglutide. Its 68-week phase 3a obesity trial randomized 3,417 adults across combination, semaglutide-alone, cagrilintide-alone and placebo groups, and reported −20.4% mean weight change with the combination against −3.0% on placebo, alongside gastrointestinal adverse events in 79.6% of the combination group against 39.9% on placebo.^[4] A secondary, post hoc analysis of that same trial reports the four-arm comparison directly: 30.3%, 19.1%, 9.0% and 3.3% of the combination, semaglutide, cagrilintide and placebo groups reached both anthropometric targets at week 68.^[5] In type 2 diabetes, the corresponding phase 3 trial met its primary endpoint against semaglutide alone by −0.16 percentage points of glycated haemoglobin (95% CI −0.27 to −0.05, p=0.0035), at 86.9% versus 81.2% adverse events.^[6] Every one of those numbers describes cagrilintide and semaglutide. None of them describes cagrilintide and retatrutide, and moving a figure from the first sentence to the second is the single most consequential error available on this page.

The structural reason the substitution does not work. Retatrutide is Eli Lilly's molecule and cagrilintide is Novo Nordisk's. Each company has run its own amylin-plus-incretin programme using its own two molecules: Novo Nordisk's is cagrilintide with semaglutide, and Lilly's is the amylin analogue eloralintide, whose registered studies were queried on the ClinicalTrials.gov API v2 on 1 September 2026 — query.intr=eloralintide returned 17 studies and query.term=LY3841136 returned 20, a union of 21 distinct registrations, every one of them sponsored by Eli Lilly and Company, and the combination partner is tirzepatide or macupatide in every case where one appears and never retatrutide. Both real programmes exist; neither is the combination this page is named for.

The combination claim above is graded anecdotal for a plain reason. There is no human trial, no animal study and no in vitro experiment of these two molecules given together, so there is nothing for a stronger grade to rest on. Evidence about retatrutide plus evidence about cagrilintide is not evidence about retatrutide with cagrilintide.

Where the evidence is weak

The two halves of the name are not in the same evidence-certainty stratum. A systematic review and network meta-analysis of 262 randomized trials in 99,791 participants, applying GRADE, places cagrilintide-semaglutide at −14.8% (95% CI −16.9 to −12.7) on moderate-to-high certainty evidence and retatrutide among "emerging agents" at 13.1% to 14.6% on very low to low certainty evidence.^[1] Averaging a well-characterized combination and a low-certainty single agent into one expectation is not conservative; it is an invention.

The rankings that flatter cagrilintide are rankings of the other combination. The amylin-focused network meta-analysis places high-dose cagrilintide-semaglutide third, behind amycretin and behind Lilly's own eloralintide, and reports that only high-dose cagrilintide-semaglutide increased adverse-event-related discontinuation. Its authors describe the underlying data as sparse and low-certainty and their own findings as preliminary.^[7]

Neither component's tolerability record is reassuring at the top of its range, and there is no way to add them. Gastrointestinal events were dose-related in the retatrutide phase 2 trial,^[2] were the most frequent adverse events in the cagrilintide phase 2 trial,^[3] and reached 79.6% in the cagrilintide-semaglutide combination group.^[4] What two appetite-suppressing agents do to a person's gastrointestinal tract at the same time has been measured for one specific combination and for no other.

Neither molecule has outcome data, and neither has a stopping study. Retatrutide's published record ends at 48 weeks,^[2] and the largest synthesis available found that only one drug in the whole obesity field was associated with reduced all-cause mortality, and it was subcutaneous semaglutide rather than either molecule on this page.^[1]

Dosing and protocol ranges live on the individual compound pages, not here. This page carries no schedule, no sequencing and no amounts, and there is no honest way to construct one: no regulator has approved either molecule, no label exists for either, and no sponsor has run a trial of the two of them.

Questions to bring to a provider

The useful version of this conversation is not "is this combination better." It is "which published result is actually being described, and about which two molecules."

• Which trial is the figure under discussion from? The −20.4% mean weight change belongs to the 68-week phase 3a trial of cagrilintide with semaglutide.^[4] No trial of cagrilintide with retatrutide has been published at all.
• Retatrutide is an agonist at three receptors — glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1 and glucagon.^[2] What does that change relative to an approved single- or dual-receptor option?
• The largest GRADE-rated synthesis places retatrutide among "emerging agents" at very low to low certainty while rating cagrilintide-semaglutide moderate to high.^[1] What would have to be true for the first to be preferred over the second?
• Gastrointestinal disorders were the most frequent adverse events in the cagrilintide phase 2 trial,^[3] and gastrointestinal events were dose-related in the retatrutide phase 2 trial.^[2] How would tolerating both at once be recognized, and where is the line at which it stops?
• The amylin-focused network meta-analysis describes the data underneath its own rankings as sparse and low-certainty and its findings as preliminary.^[7] Neither molecule has published data on what happens after it is stopped. How should that gap weigh against an approved drug whose withdrawal data exist?

Anti-doping status

Neither component of this combination is named anywhere in the World Anti-Doping Agency Prohibited List in force for 2026. That List was retrieved on 1 September 2026 from the World Anti-Doping Agency's own file server, by way of the United States Anti-Doping Agency's prohibited-list page, and searched directly: the strings "retatrutide", "cagrilintide", "amylin", "glucagon" and "GLP" each returned zero occurrences in its text, as did "retatrutide" and "cagrilintide" in the 2026 Monitoring Program and the 2026 Explanatory Note retrieved the same day. That is a statement about three documents on one date, recorded uncited because it is a reading of the documents themselves and not of any research paper.

Not being named is not the same as being permitted, and on this combination the distinction is unusually live. Section S0 of the same List is written as a criterion rather than as a catalogue: it reaches any pharmacological substance not addressed by another section of the List and with no current approval by any governmental regulatory health authority for human therapeutic use, and its own text gives drugs under pre-clinical or clinical development as an example of what that means. Both molecules named on this page are exactly that. Their published human records are sponsor-run trials of investigational material,^[2][3] and no approval was found for either at any regulator. Substances in the S0 class are Specified Substances, which carries different sanctioning consequences from the non-Specified classes.

The 2026 Monitoring Program, read on the same date, lists markers of semaglutide and tirzepatide in and out of competition, and the 2026 Explanatory Note clarifies that the urine monitoring of semaglutide includes tirzepatide. Monitoring is not prohibition, neither of those two molecules is a component of this combination, and neither statement reaches retatrutide or cagrilintide.

An athlete subject to testing should treat an unapproved investigational agent as a question for their national anti-doping organization rather than as a settled absence. The List is reissued annually and its sections renumber between editions, so anyone competing should confirm the year in force directly rather than relying on this page.