Every jump in obesity-drug efficacy has come from stacking one more receptor. Semaglutide hit one, tirzepatide two, retatrutide three. Bioglutide — development code NA-931 — is chasing a fourth, and it does it in a form the others don't: a pill. The community has already nicknamed it "GLP-4."
The twist isn't just the count. Bioglutide's fourth target is the IGF-1 receptor, the muscle-preservation pathway — and the ADA 2025 abstract was titled around exactly that idea: weight loss without muscle loss. Here is what the trials have actually reported, how the design differs from retatrutide, and the accessible compound that covers most of the same ground today.
Research-context information only. Bioglutide (NA-931) is an investigational drug not approved by the FDA. Protocols, doses, and reactions reported below come from published clinical trials, company presentations, and self-reported community sources. This article reports what has been documented, not what should be done. Possession or use of investigational drugs outside an authorized clinical trial may be illegal in your jurisdiction. Consult a licensed physician for personal medical decisions.
What Bioglutide (NA-931) Is
Bioglutide is an investigational obesity compound, carried under the code NA-931. Two things set it apart from the injectable incretin peptides most readers know.
First, the receptor design. NA-931 is described as a quadruple agonist hitting four receptors: IGF-1, GLP-1, GIP, and glucagon. That is retatrutide's three incretin-axis targets plus the IGF-1 receptor. The ADA 2025 oral-presentation abstract (143-OR, published in the journal Diabetes) is titled "NA-931, a Novel Quadruple IGF-1, GLP-1, GIP, and Glucagon Receptor Agonist Reduces Body Weight without Muscle Loss."
Second, the format. NA-931 is described as an oral, once-daily, food-independent small molecule — not an injectable peptide. There is no reconstitution, no needles, and no meal-timing requirement in how it has been characterized.
The "GLP-4" label the community uses is a colloquial nod to the four-receptor count — one more than retatrutide's three. It is not an official drug name, and there is no receptor called GLP-4.
The Quadruple Mechanism: Why IGF-1 Is the New Piece
Three of bioglutide's four targets are the same axis retatrutide works: GLP-1, GIP, and glucagon drive appetite suppression, insulin/glucose handling, and energy expenditure. The fourth target — the IGF-1 receptor — is the differentiator, and it points at a problem the whole obesity-drug field is now focused on.
Aggressive incretin-driven weight loss tends to strip lean mass alongside fat. The industry response has been to add a mechanism that protects muscle. The framing is that engaging the IGF-1 receptor — a pathway tied to muscle anabolism — is what let NA-931 reduce body weight while sparing lean tissue in its studies. That is the entire thesis behind the abstract title, and the Phase 2 readout reported "no muscle loss" as a finding (abstract 2189-LB, Diabetes, 2025).
How that IGF-1 signal balances against the appetite and energy-expenditure arms is exactly the kind of question human trials exist to answer, and the reported "without muscle loss" result is a conference readout, not a peer-reviewed journal analysis. It is a stated finding to watch, not a settled one.
The Oral Advantage
Most of the high-efficacy obesity compounds — semaglutide, tirzepatide, retatrutide, cagrilintide — are injectables. An oral small molecule that reaches comparable weight-loss numbers would remove the two biggest friction points in the category: the needle and the cold chain.
NA-931 is characterized as once-daily and food-independent, meaning no fasting window or dosing-with-food rule of the kind that constrained the first oral GLP-1 attempts. If that profile holds up in larger trials, the practical difference for the field is less about raw efficacy and more about who is willing to start and stay on treatment. Oral dosing is a compliance story as much as a pharmacology one.
The caveat is that oral peptide-adjacent compounds have historically struggled with absorption and bioavailability, which is why most of the class went injectable in the first place. Bioglutide being a small molecule rather than a peptide is part of how its oral route is framed — but the durability of that advantage is a trial question, not a settled result.
Affiliate disclosure: The Peptide Catalog earns a commission on purchases made through the vendor links below.
Bioglutide isn't in our vetted vendor lineup yet. Retatrutide is the closest researched compound sharing three of bioglutide's four receptor targets (GLP-1, GIP, glucagon) and is currently stocked by research vendors — though no data shows it reproduces bioglutide's specific IGF-1-linked results. Compare current pricing and COA-verified vendors below.
Compare Top Peptides
Best vendor pricing, COA verified, with active discount codes
Where Bioglutide Sits: Retatrutide vs Bioglutide vs VRX-0075
The clearest way to place bioglutide is on the receptor-count ladder the field has been climbing.
- Retatrutide — a triple agonist (GLP-1, GIP, glucagon). It is the most advanced high-efficacy obesity compound in accessible research-vendor catalogs, with Phase 3 data still accumulating. It is the practical benchmark bioglutide gets compared to.
- Bioglutide (NA-931) — a quadruple agonist ("GLP-4"). Its differentiator versus retatrutide is two-fold: it adds the IGF-1 muscle-preservation target, and it is oral rather than injectable. Critically, human Phase 1 and Phase 2 data have been reported for it — putting it further along the clinical path than most experimental multi-agonists.
- VRX-0075 — a quintuple agonist ("GLP-5"), adding amylin and calcitonin on top of the incretin trio. As covered in our VRX-0075 breakdown, it is still a rat-only, preclinical readout with no human data.
So the ladder isn't purely "more receptors is more proven." VRX-0075 has more targets on paper but only rodent data. Bioglutide has fewer targets than VRX-0075 but the thing that actually matters for a compound's odds — human Phase 1 and Phase 2 results, plus an oral route — which is what makes it worth tracking distinctly from the preclinical field.
What the Trials Reported
The efficacy numbers below are all conference-reported — presentations at ADA 2025 and a published Phase 1 paper — not independent peer-reviewed journal analyses. Each figure is attributed to its source.
Phase 2. The Phase 2 trial reported at ADA 2025 (abstract 2189-LB; trial registered as ClinicalTrials.gov NCT06564753) a 13-week, randomized, double-blind, placebo-controlled study in 125 adults with a BMI of at least 30, or at least 27 with a weight-related comorbidity. At the 150 mg/day dose, the trial reported a 13.8% mean weight loss (12.4% placebo-adjusted), with 72% of participants reaching at least 12% weight loss versus 2% on placebo. Gastrointestinal effects were reported as mild — nausea/vomiting at 7.3% and diarrhea at 6.3% — and no muscle loss was reported.
Phase 1. Phase 1 results, published in Endocrine Practice, reported roughly 10–13% weight loss at 12 weeks.
Two framing points matter for reading these figures. First, they come from conference presentations and one journal paper, not a body of independent replication — the Phase 2 weight-loss numbers in particular were reported at a conference. Second, GI tolerability is the historical make-or-break variable for every compound in this class, so the reported mild GI profile is a claim worth watching validate in larger trials rather than treating as settled.
What to Watch Next
- Peer-reviewed Phase 2 publication. The 13.8% figure reported at ADA 2025 lives in a conference abstract. A full peer-reviewed paper with the complete safety and dropout data is the next credibility gate.
- Whether the IGF-1 "no muscle loss" claim holds. The muscle-preservation angle is bioglutide's headline differentiator. Independent body-composition data (DEXA or similar) at scale is what would confirm it.
- The oral route at higher exposures. Small-molecule oral dosing has to hold its absorption advantage as trials scale — a real-world durability question, not a settled one.
- The researched analog in the meantime. Until bioglutide reaches the market — years away at best — retatrutide shares three of its four receptor targets and is stocked by research vendors, though no data shows it reproduces bioglutide's IGF-1-linked results. See the retatrutide dosing guide for documented protocol details.
References
| Citation |
Topic |
| ADA 2025 Scientific Sessions, abstract 143-OR (Diabetes) |
NA-931 quadruple IGF-1/GLP-1/GIP/glucagon agonist reduces body weight without muscle loss |
| ADA 2025 Scientific Sessions, abstract 2189-LB (Diabetes) |
NA-931 Phase 2: 13.8% mean weight loss at 150 mg/day, GI tolerability, no muscle loss |
| ClinicalTrials.gov NCT06564753 |
NA-931 Phase 2 registration — 13-week randomized, double-blind, placebo-controlled, 125 adults |
| Endocrine Practice — NA-931 Phase 1 |
NA-931 Phase 1: ~10–13% weight loss at 12 weeks |
This article reports on an investigational research compound. Bioglutide (NA-931) is not approved by the FDA, its efficacy figures are conference-reported, and it is not available for purchase. Nothing here constitutes medical advice. Consult a licensed clinician for treatment decisions.