Danuglipron (PF-06882961)
Pfizer's discontinued oral non-peptide GLP-1 receptor agonist — an instructive case study in oral-GLP-1 development.
At a glance
What it is: Pfizer's discontinued oral non-peptide GLP-1 receptor agonist — an instructive case study in oral-GLP-1 development..
Primary research applications:
- Type 2 diabetes (Phase 2 — discontinued)
- Obesity (development discontinued April 2025)
Editorial summary: Danuglipron was Pfizer's lead oral non-peptide GLP-1, advancing through Phase 2 with credible weight-loss and glycemic data. Development was discontinued in April 2025 following a hepatic safety signal in a single trial participant. The molecule is an instructive case study in the challenges of bringing oral non-peptide GLP-1s to market — and a useful contrast to the orforglipron program.
- Class / structure
- Small-molecule (non-peptide) GLP-1 receptor agonist
- Half-life
- Designed for twice-daily and (later) once-daily dosing
- First described
- Late 2010s (Pfizer)
- Regulatory status
- Development discontinued (April 2025)
What is Danuglipron?
Danuglipron was an investigational small-molecule GLP-1 receptor agonist developed by Pfizer. It activated the GLP-1 receptor through small-molecule chemistry similar in concept to orforglipron, with downstream effects characteristic of the GLP-1 class.
Discovery and development
Danuglipron was Pfizer's lead oral non-peptide GLP-1 program, advanced into Phase 2 obesity and T2D trials with twice-daily and later once-daily formulations under development. The program was paired with another Pfizer oral GLP-1 candidate, lotiglipron, which had been discontinued earlier following a hepatic enzyme signal.
In April 2025, Pfizer announced discontinuation of danuglipron development after a Phase 3-relevant safety review noted a case of probable drug-induced liver injury in a single trial participant. The decision was widely reported as a significant setback for Pfizer's metabolic franchise and as a cautionary data point for the oral non-peptide GLP-1 class.
Mechanism of action
Same GLP-1 receptor agonism as the peptide and small-molecule GLP-1 class — appetite suppression, slowed gastric emptying, glucose-dependent insulin secretion.
Pharmacokinetics
Earlier formulations were given twice daily; the once-daily formulation was being developed prior to discontinuation.
What the research shows
The peer-reviewed literature on Danuglipron is summarized below across two tiers: human research (the highest standard), and preclinical / emerging research (animal models and early-stage human work).
Claims and the evidence behind them
This table summarizes commonly discussed claims and how the published evidence weighs in. The aim is clarity — supported claims, claims that look promising but need more data, and claims that outrun the science.
| Claim | What the evidence shows | Verdict |
|---|---|---|
| Demonstrated weight loss and glycemic effects in Phase 2 | Phase 2 readouts | Supported |
| Will reach the market | Discontinued April 2025 | Unsupported |
| All oral non-peptide GLP-1s carry hepatic safety risk | Inferential — orforglipron's Phase 3 hepatic safety profile is being closely watched | Uncertain |
Reported user experiences
How the research describes administration
Phase 2 and 3 trial protocols used oral dosing. The drug is no longer in active development.
Editorial note
Administration details above describe how the peptide is given in published studies. We summarize this for educational completeness — these descriptions are not protocols, dosing recommendations, or instructions for personal use. Decisions about treatment require an appropriately licensed clinician.
Safety considerations and open questions
The takeaway
Danuglipron is the most prominent recent example of how a credible Phase 2 program in this space can fail at the safety-stewardship gate. Its discontinuation is part of why orforglipron's Phase 3 hepatic profile is being closely monitored, and why the oral GLP-1 class remains a story to follow rather than a settled clinical category. The molecule is preserved here as a case study for readers tracking how this field actually advances.
Frequently asked questions
Why was danuglipron discontinued?
Pfizer announced discontinuation in April 2025 after a Phase 3-relevant safety review noted a case of probable drug-induced liver injury in a single trial participant. The company concluded that continued development was not appropriate.
Is the danuglipron experience a problem for orforglipron?
The two molecules are structurally distinct, and orforglipron's Phase 3 hepatic safety has not shown the same signal in the data reported to date. Regulators will look closely at hepatic monitoring across the oral non-peptide GLP-1 class as a whole.
References
- Saxena AR, et al. Danuglipron (PF-06882961), an oral small-molecule GLP-1 receptor agonist, in adults with type 2 diabetes mellitus. JAMA Netw Open. 2023;6(5):e2314493. https://pubmed.ncbi.nlm.nih.gov/37234001/
- Saxena AR, et al. Identification of the first oral small-molecule GLP-1 receptor agonist (PF-06882961) as a candidate for type 2 diabetes mellitus. Diabetes. 2021;70(Suppl 1):109-OR. https://pubmed.ncbi.nlm.nih.gov/?term=PF-06882961+danuglipron
- Drucker DJ. Mechanisms of action and therapeutic application of glucagon-like peptide-1. Cell Metab. 2018;27(4):740-756. (Class-level reference for GLP-1 receptor agonist pharmacology.) https://pubmed.ncbi.nlm.nih.gov/29617641/