The metabolic-peptide literature has moved faster in the past twelve months than in any comparable stretch since the first GLP-1 agonists were characterized. Triple agonists posted their first pivotal data, glucagon-receptor engagement graduated from a theoretical liability to a measurable liver-fat lever, and the amylin pathway re-emerged as a distinct axis rather than a footnote. This Friday roundup collects the notable peer-reviewed and conference-reported findings of the 2025–2026 window, with sources and dates, framed for the laboratory research community.
None of what follows is a recommendation. It is a survey of where the published evidence currently sits.
Retatrutide: the first triple-agonist Phase 3 data
The single largest signal of the period came from retatrutide, Eli Lilly's GLP-1 / GIP / glucagon triple receptor agonist. After the headline-grabbing Phase 2 obesity results in 2023, the compound's TRIUMPH Phase 3 program began reporting.
TRIUMPH-4 — studying obesity with knee osteoarthritis, without type 2 diabetes — read out positive in December 2025, the first Phase 3 readout of the program, reporting roughly 28.7% mean body-weight reduction at 68 weeks on the highest investigated dose.
TRIUMPH-1 followed in June 2026: a 2,339-participant randomized, double-blind, placebo-controlled trial in which the high-dose arm produced a 28.3% mean reduction at 80 weeks, with a prespecified blinded extension reaching 30.3% by week 104. The trial also reported accompanying cardiometabolic shifts — waist circumference, non-HDL cholesterol, triglycerides, systolic blood pressure, and hs-CRP all moved in the expected direction (AJMC; Eli Lilly investor release).
The research-relevant point is the glucagon-receptor third arm. GIP and GLP-1 dual agonism was already validated; what TRIUMPH tests is whether adding glucagon agonism — historically considered counterproductive for glycemic endpoints — translates into additive energy-expenditure and hepatic effects without sacrificing tolerability. Seven additional TRIUMPH trials, including obesity plus type 2 diabetes and obesity plus established cardiovascular disease, are scheduled to report across the remainder of 2026.
Survodutide: glucagon agonism aimed at the liver
If retatrutide tests glucagon agonism for weight, survodutide — Boehringer Ingelheim's glucagon-receptor / GLP-1-receptor dual agonist — tests it for the liver specifically. The mechanistic argument is that the glucagon-receptor component drives direct hepatic fat reduction, something GLP-1 monotherapy achieves only indirectly through weight loss.
At the June 2026 American Diabetes Association Scientific Sessions, results from the SYNCHRONIZE-1 (obesity) and SYNCHRONIZE-MASLD Phase 3 trials were presented under "The Benefits of Glucagon/GLP-1 Receptor Dual Agonism." SYNCHRONIZE-MASLD enrolled 216 adults with obesity and at-risk metabolic dysfunction-associated steatotic liver disease, randomized 2:1 to survodutide or placebo, and reported significant weight loss alongside liver-fat reduction (Nature Medicine; ADA Meeting News).
Survodutide holds FDA Breakthrough Therapy Designation for non-cirrhotic MASH and is advancing through both the SYNCHRONIZE (obesity) and LIVERAGE (MASH/MASLD) programs. For researchers tracking the steatotic-liver-disease literature, it represents the cleanest current test of whether glucagon-receptor engagement adds a liver-specific effect on top of GLP-1.
CagriSema and the amylin combination story
The amylin axis produced two distinct threads. The first is combination: CagriSema, a co-formulation of the long-acting amylin analog cagrilintide with semaglutide.
The Phase 3 REDEFINE 1 and REDEFINE 2 results were published in the New England Journal of Medicine in June 2025 and presented at the ADA's 85th Scientific Sessions. REDEFINE 1, a 68-week trial in 3,417 adults with obesity or overweight without type 2 diabetes, reported an average 20.4% body-weight reduction with CagriSema versus 14.9% with semaglutide alone, 11.5% with cagrilintide alone, and 3% with placebo. Adjusted for full adherence, the CagriSema figure rose to 22.7% (NEJM; ACC summary).
The signal here is additivity across distinct receptors. Amylin and GLP-1 act through separate pathways — amylin centrally modulates satiety and gastric emptying via the area postrema, GLP-1 through its own receptor population. The combination's separation from either monotherapy is the data point that matters: it suggests the two axes are not redundant.
The amylin axis as a standalone target
The second amylin thread is monotherapy, and it is where the newest 2026 data sits. The interest is partly tolerability — amylin analogs have so far shown a gentler gastrointestinal profile than high-dose incretins — and partly the prospect of less frequent dosing.
- Petrelintide (Zealand Pharma/Roche), a long-acting amylin analog, reported up to 10.7% mean reduction at week 42 versus 1.7% placebo in the ZUPREME-1 Phase 2 trial. Roche announced positive Phase 2 results in March 2026, with Phase 3 planned for the second half of 2026 and a petrelintide combination study to follow (Roche release; Zealand pipeline).
- Maridebart cafraglutide (Amgen's "MariTide"), an amylin/GLP-1 combination molecule engineered for a once-monthly profile, reported up to 20% weight loss in its Phase 2 trial and is advancing to Phase 3, including arms in cardiovascular disease, heart failure, and obstructive sleep apnea (AJMC).
For the catalog, the relevant standalone amylin tool is cagrilintide — the molecule whose monotherapy arm in REDEFINE 1 provides a published reference point for amylin-alone effects.
What the period actually establishes
Reading these readouts together, a few research-level themes are worth isolating:
Receptor stacking is producing additive, not merely larger, effects. Each successful program adds a mechanistically distinct receptor — GIP, glucagon, amylin — and the monotherapy comparator arms (where they exist) suggest the axes contribute somewhat independently rather than saturating a single pathway.
Glucagon agonism has been rehabilitated. Long treated as a glycemic liability, glucagon-receptor engagement is now the differentiating feature of both retatrutide (energy expenditure, weight) and survodutide (hepatic fat). Whether the two applications generalize is an open question the 2026 readouts will sharpen.
Tolerability and dosing cadence are becoming endpoints in their own right. The amylin programs are competing less on peak efficacy than on gastrointestinal profile and dosing frequency — a shift in what the literature is being designed to measure.
These are clinical-trial datasets in human therapeutic development. They are cited here as published pharmacology, not as guidance. The compounds referenced exist in the Trulogic catalog as research-use-only reference materials; for how identity and purity of such materials are established before they enter any protocol, see /quality/, and for background on each compound class see the /library/.
FAQ
Are these trial weight-loss figures applicable outside the clinical setting? No. The percentages reported above are endpoints from controlled human clinical trials with defined protocols, monitoring, and titration. They describe the studies, not any individual outcome, and are reproduced here only as literature.
Why group incretins and amylins together? Because the 2025–2026 readouts increasingly combine them. The frontier compounds either stack incretin receptors (retatrutide, survodutide) or pair an incretin with amylin (CagriSema, maridebart cafraglutide), making the two axes difficult to discuss in isolation.
Which of these are in the Trulogic catalog? Retatrutide, survodutide, semaglutide, cagrilintide, tirzepatide, and the CagriSema blend are catalogued as research compounds. Petrelintide and maridebart cafraglutide are investigational and included here for literature context only.
This article is educational and for the laboratory research community. Trulogic Labs products are sold for laboratory and research use only and are not for human consumption.