GLP-RT — WHAT DOES IT DO?
GLP-RT activates three receptors on cells: GLP-1, GIP, and glucagon receptors. These receptors receive hormone signals that help coordinate blood sugar, appetite, and energy use.
Activates three cellular signals
One peptide can activate three different receptor types. It is called a triple agonist because it turns on signaling through all three. [1]
Engages glucose-regulating pathways
GLP-1 and GIP receptor pathways help regulate insulin secretion in response to glucose. Researchers study how their combined activation changes glucose control. [1]
Adds glucagon-receptor activity
The glucagon pathway is involved in fuel metabolism. Discovery experiments linked its activation to increased energy expenditure in mice. [1]
Changes receptor signaling
Structural research shows how GLP-RT binds each receptor and forms signaling complexes with Gs proteins, which carry signals into the cell. [2]
How three metabolic receptor pathways work together to influence glucose control, food intake, and energy balance.
What is GLP-RT?
GLP-RT, also known as LY3437943, is a synthetic peptide designed to activate the receptors for glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon. Its design combines three hormone-signaling pathways in one molecule. [1]
The discovery study reported activity at all three receptors, with greater activity at GIP receptors than at GLP-1 and glucagon receptors in its laboratory assays. Researchers investigate how this balance affects metabolic outcomes. [1]
Research spans receptor and structural experiments, preclinical studies, and human clinical trials. The major clinical questions include body-weight change, glucose control, and tolerability.
What researchers are studying.
Three targets, one peptide
How GLP-RT activates GLP-1R, GIPR, and GCGR and how their signals combine. [1, 2]
Glucose and energy balance
Changes in glucose control, food intake, and energy expenditure. [1]
Body-weight change
Measured weight changes over months of treatment compared with placebo. [3, 4]
Tolerability
Gastrointestinal adverse events, heart-rate changes, and treatment discontinuations are important outcomes alongside efficacy. [3, 4]
What the studies found.
Selected papers connecting the cellular mechanism with clinical findings. Open the originals for methods, participant details, and full results.
Discovery of the triple agonist
Coskun et al. · Cell MetabolismDemonstrated activity at glucagon, GIP, and GLP-1 receptors. In obese mice, the compound reduced weight and improved glucose control; the paper also reported early human proof of concept.
Read original study ↗Full paper title
LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: From discovery to clinical proof of concept
How the peptide fits three receptors
Original research · Cell DiscoveryUsed structural and functional approaches to examine GLP-RT-bound receptor signaling complexes. This connects the peptide’s molecular interactions with its triple-receptor activity.
Read original study ↗Full paper title
Structural insights into the triple agonism at GLP-1R, GIPR and GCGR manifested by GLP-RT
Body-weight change and tolerability
Jastreboff et al. · New England Journal of MedicineIn 338 adults, the trial measured weight reduction over 48 weeks and recorded gastrointestinal adverse events and heart-rate changes.
Read original study ↗Full paper title
Triple-Hormone-Receptor Agonist GLP-RT for Obesity — A Phase 2 Trial
Longer-term clinical outcomes
Jastreboff et al. · New England Journal of MedicineAn 80-week placebo-controlled trial in adults with obesity without diabetes reported weight reduction and improvements in pain and apnea-hypopnea outcomes. Gastrointestinal events were the most common adverse events. See the original report for complete results.
Read original study ↗Full paper title
GLP-RT, a Triple Hormone Receptor Agonist, for Treatment of Obesity
Clinical findings in context.
At 48 weeks, the 12-mg trial group had a mean weight reduction of 24.2%, compared with 2.1% with placebo. These are group averages from a controlled trial, not a prediction for an individual or a catalog product. [3]
The most common adverse events were gastrointestinal and were generally mild to moderate. Dose-dependent heart-rate increases peaked at 24 weeks and declined afterward. [3]
A 2026 phase 3 publication extends the clinical evidence to an 80-week trial and reports weight reduction and outcomes relating to pain and sleep apnea. Its full report is linked below rather than substituting early phase 2 figures for later results. [4]
What these studies can tell us.
Cell and structural studies explain receptor activation. Clinical trials measure the resulting outcomes across people and also record adverse events. The trial population, duration, analysis method, and comparator matter when interpreting results.
A closer look at the evidence.
What does “triple agonist” mean at a cellular level?
It means GLP-RT can activate three receptor types—GLP-1R, GIPR, and GCGR. Receptors act as signal receivers on cells. Activating them initiates signaling inside the cell; the effects depend on the receptor and tissue involved. [1] [2]
How does GLP-RT connect with energy use and body weight?
Its discovery experiments linked GLP-1 and GIP receptor activity with reduced food intake, while glucagon receptor activity added an energy-expenditure component in mice. The phase 2 human trial then measured substantial body-weight reductions. The cellular and clinical results describe different levels of the same research question. [1] [3]
What adverse findings have human studies reported?
The phase 2 obesity trial reported gastrointestinal events as the most common adverse effects, generally mild to moderate and dose-related. It also reported dose-dependent increases in heart rate that peaked at 24 weeks and later declined. The newer phase 3 report likewise identifies gastrointestinal events as most common. [3] [4]