Visepegenatide
Visepegenatide, PEGylated exenatide for once-weekly injection (development code PB-119)
Written by Aaron CuhaReviewed Sep 2026
Also known as: PB-119, PEGylated exenatide, PEGylated exenatide injection
A published phase 3 in 273 treatment-naive Chinese adults cut glycated haemoglobin 1.36 percentage points against 0.63 on placebo at 24 weeks, and it needs no dose titration. In its phase 1 study 28 percent of healthy volunteers developed antidrug antibodies.
Overview
Visepegenatide is exenatide with a polyethylene glycol chain attached, which turns a twice-daily injection into a once-weekly one. It comes from PegBio in Hangzhou and carried the development code PB-119 through most of its published literature.
The selling point in the trial reports is not the size of the glycaemic effect, which is ordinary for the class, but that it is given at a fixed dose with no titration. Every other weekly GLP-1 agonist requires a dose escalation over weeks to keep nausea tolerable. The phase 3 investigators argue that gastrointestinal events were less common here than with other weekly agonists, though no trial compared them directly.
The phase 3 ran 24 weeks double-blind followed by a 28 week extension in which everyone received active drug, so the 52 week figures are uncontrolled beyond week 24.
The fact that most coverage omits is immunogenicity. In the multiple ascending dose phase 1 study, 10 of 36 healthy volunteers developed specific antibodies after six weekly injections, and antibody-positive subjects had measurably different pharmacokinetics. PEGylated and protein-based long-acting agonists have a history here: exenatide once weekly and the discontinued albiglutide both carried antibody findings. The phase 3 report does not resolve what that means over years of use.
Mechanism of action
Exenatide, a synthetic version of exendin-4 from Gila monster venom that acts as a GLP-1 receptor agonist, covalently modified with polyethylene glycol. The PEG chain increases hydrodynamic radius and slows renal clearance, extending half-life from the few hours of native exenatide to around 55 hours, which supports weekly dosing at a fixed dose. Receptor pharmacology is unchanged: glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, reduced appetite. Published pharmacodynamic analysis using an oral minimal model reports improvement in beta cell function parameters and in an insulin sensitivity parameter, though the simpler homeostatic model assessment measure of insulin resistance did not change significantly.
Human evidence
One published placebo-controlled phase 3 in 273 treatment-naive Chinese adults, a 251 patient phase 2, a phase 1 multiple ascending dose study and a small mechanistic study. Development also included a phase 2 in the United States, which the phase 3 report references.
- Phase 3, 24 weeks: glycated haemoglobin fell 1.36 percentage points against 0.63 on placebo, with 50.4 percent versus 14.2 percent reaching below 7.0 percent.
- The 52 week figures come from an extension in which the placebo group crossed over to active drug, so there is no controlled comparison past week 24.
- Phase 2, 12 weeks: the 150 microgram dose outperformed the 200 microgram dose on glycated haemoglobin, which is why the middle dose was carried forward.
- Phase 1: 27.78 percent of healthy volunteers developed antidrug antibodies after six weekly doses, with altered pharmacokinetics in antibody-positive subjects.
- Weight loss was modest and BMI-dependent, reaching 4.77 kg at week 52 in participants with BMI above 32, reported with a standard deviation of 13.94 kg.
What this does not tell you: The controlled period is 24 weeks. The claim that it causes less gastrointestinal upset than other weekly agonists is a comparison to external trials, not a head to head. The immunogenicity finding comes from 36 healthy volunteers over six weeks and has not been followed out to the years a diabetes drug is actually taken. There is no cardiovascular outcome trial. And the weight loss figure most often quoted carries a standard deviation three times its own size, which means the average is being carried by a subset.
Reading the research record
Two things on this page deserve more attention than they get.
The first is the dose-response in phase 2. The 150 microgram dose lowered glycated haemoglobin more than the 200 microgram dose. That is not what a clean dose-response looks like, and the trial was not powered to distinguish them, but it is the reason the middle dose became the marketed one. Selecting a dose off a non-monotonic phase 2 curve is common and it is worth knowing when it has happened.
The second is immunogenicity, which is a structural issue rather than a manufacturing one. Exenatide is a lizard peptide, not a human one, and attaching polyethylene glycol adds another epitope. Antibodies to exenatide-based products are a known phenomenon, and the developer's own phase 1 found them in more than a quarter of healthy volunteers after six weeks, with measurable effects on drug exposure. The published phase 3 does not report an antibody analysis in its abstract. Anyone weighing this drug against a human-sequence analogue should want that number over a year, not over six weeks.
A note on what Chinese approval does and does not tell you. China's National Medical Products Administration requires trials in Chinese patients, and the pivotal trials behind these approvals are real randomised controlled trials published in mainstream journals, several of them in Diabetologia, Nature Communications, Diabetes Obesity and Metabolism and the Lancet regional title. What is usually missing compared with the Western incretin programmes is a cardiovascular outcome trial. Semaglutide and liraglutide carry cardiovascular outcome data in tens of thousands of patients followed for years; none of the compounds on this page does. So the correct statement is that these drugs are shown to lower glycated haemoglobin and body weight in Chinese adults over months, not that they are shown to prevent heart attacks. That gap is a real difference in the evidence, and it is separate from the question of whether a Western reader has heard of the drug.
The evidence, charted
Fig. 1 · evidence composition
4of 4 citations (100%) are in people
Every citation cited here is Human work; no other study type is cited on this page. This count is of our own citation list and understates any literature larger than the sources we cite.
Fig. 2 · evidence over time
Evidence spans 3 distinct years, 2021 to 2024, counted from the citation list on this page.
Fig. 3 · legal status at a glance
US
Not approved
UK
Not approved
AU
Not approved
CA
Not approved
Not approved in any of the four jurisdictions shown. A jurisdiction's classification is a regulatory fact, not a verdict on the science; see Legal status below for the full text and any notes.
Fig. 4 · dose response
No human dose response curve exists
We draw this figure where the data supports it. For this compound in humans it does not, so the panel stays empty rather than borrowing an animal curve and implying it transfers.
Key studies & citations
- Human2024
Efficacy and safety of visepegenatide, a long-acting weekly GLP-1 receptor agonist as monotherapy in type 2 diabetes mellitus: a randomised, double-blind, parallel, placebo-controlled phase 3 trial
273 treatment-naive adults at 30 Chinese centres, randomised 1:1 to 150 micrograms weekly or placebo for 24 weeks, then all on active drug to week 52. At week 24 glycated haemoglobin fell 1.36 percentage points against 0.63 on placebo, a difference of 0.73 points. 50.4 percent reached below 7.0 percent against 14.2 percent. Rescue therapy was needed by 3 participants on drug against 17 on placebo. Weight loss was reported as BMI-dependent and reached 4.77 kg at week 52 in those with BMI above 32, with a standard deviation of 13.94 kg, which is wide enough to warrant caution. Funded by PegBio.
The Lancet Regional Health Western Pacific - Human2021
Efficacy and safety of PEGylated exenatide injection (PB-119) in treatment-naive type 2 diabetes mellitus patients: a Phase II randomised, double-blind, parallel, placebo-controlled study
251 treatment-naive Chinese patients randomised to placebo or 75, 150 or 200 micrograms weekly for 12 weeks. Glycated haemoglobin differences against placebo were 0.72, 1.18 and 1.02 percentage points, with the middle dose performing best rather than the highest, which is why 150 micrograms went forward. No treatment-emergent serious adverse event, severe hypoglycaemia or death. Note that this paper has a published correction.
Diabetologia - Human2021
Safety, Pharmacokinetics and Pharmacodynamics of Multiple Escalating Doses of PEGylated Exenatide (PB-119) in Healthy Volunteers
Twelve healthy volunteers per group received weekly subcutaneous injections at 165, 330 or 660 micrograms for six weeks. Half-life was approximately 55 to 57 hours across all three doses. 10 of 36 subjects, 27.78 percent, developed specific antibodies, and antibody-positive subjects had higher average and maximum concentrations but lower clearance, half-life and accumulation index. Adverse events clustered in the top dose group, 8 of 12 subjects reporting 16 events, mostly gastrointestinal. The authors conclude that pharmacokinetics may be affected by immunogenicity.
European Journal of Drug Metabolism and Pharmacokinetics - Human2023
PEGylated exenatide injection (PB-119) improves beta-cell function and insulin resistance in treatment-naive type 2 diabetes mellitus patients
36 Chinese patients randomised to 25 or 50 micrograms weekly or to twice-daily exenatide for 12 weeks, with oral mixed meal tolerance tests modelled to estimate beta cell function and insulin sensitivity. Both treatments raised beta cell function parameters, disposition index and insulin secretion rates against their own baseline. The high dose improved a modelled insulin sensitivity parameter, but the simpler homeostatic model assessment of insulin resistance showed no significant change within or between treatments. A 36 person mechanistic study, not an efficacy trial.
Frontiers in Pharmacology
Frequently asked questions
What is the difference between visepegenatide and exenatide?
It is the same molecule, exendin-4, with a polyethylene glycol chain attached. That slows clearance and turns a twice-daily injection into a once-weekly one with a half-life of about 55 hours. The receptor pharmacology is unchanged.
Why does it not need titration?
Its developers give it at a fixed weekly dose and report gastrointestinal events less frequent than with other weekly agonists, which is the stated rationale. No trial has compared it head to head against a titrated agonist, so the claim rests on comparison with separate trials.
Should I worry about antibodies?
It is the open question on this compound. In the phase 1 study 10 of 36 healthy volunteers developed specific antibodies after six weekly injections, and their drug exposure differed measurably from antibody-negative subjects. Nobody has published what that looks like after a year of treatment, which is the timeframe that matters for a diabetes drug.
Can I get it outside China?
No. It has no approval in the United States, United Kingdom, Australia or Canada. A phase 2 study was conducted in the United States but no Western regulatory filing has been located.
How much weight will it cause me to lose?
Less than the drugs marketed for obesity. The phase 3 reports a mean 4.77 kg reduction at 52 weeks in participants with a BMI above 32, with a standard deviation of 13.94 kg, and smaller effects at lower BMI. It is a glycaemic drug with a weight effect, not a weight loss drug.