NA-931 vs Petrelintide
Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research
Also: Bioglutide, cyclic glycine-proline
NA-931 (Bioglutide) is cyclic glycine-proline, a two-amino-acid ring that occurs naturally as a breakdown product of IGF-1. Its developer, Biomed Industries, describes it as an oral once-daily agonist at four receptors at once - IGF-1, GLP-1, GIP and glucagon - and has reported 13 to 15 percent weight loss in a 126-person Phase 2 trial. Those numbers have only ever appeared in conference abstracts, never in a peer-reviewed paper, and no trial results have been filed to ClinicalTrials.gov. The same molecule is already sold as a consumer brain-health supplement and as a Sigma-Aldrich catalogue chemical, which makes it unusually cheap to source and unusually hard to verify.
Also: ZP8396
Petrelintide is a long-acting amylin analog from Zealand Pharma, co-developed with Roche, designed as a once-weekly injection for obesity. The pitch is gentler weight loss than GLP-1 drugs but with far less nausea and vomiting. Two phase 2 trials read out positively in 2026 (up to 10.7% weight loss at 42 weeks), and a roughly 7,000-person phase 3 program has started. It is not approved anywhere.
Key Comparison Insights
- Both peptides belong to the Weight Loss category, suggesting similar primary applications.
Detailed Comparison
| Attribute | NA-931 | Petrelintide |
|---|---|---|
| Category | Weight Loss | Weight Loss |
| FDA Status | Not FDA Approved | Not FDA Approved |
| Clinical Status | Pre I II III IV FDA | Pre I II III IV FDA |
| Mechanism of Action | Cyclic glycine-proline is a diketopiperazine: glycine and proline joined into a small ring, 154 daltons, roughly a thirtieth the size of tirzepatide or retatrutide. The independent literature, mostly from Jian Guan's group in Auckland, describes a single mechanism: cGP competes with IGF-1 for binding to IGFBP-3, which frees up IGF-1 that was otherwise bound and inactive. That is a bioavailability effect, studied for stroke recovery, Parkinson's and blood pressure rather than for weight. Biomed's own patent filing (WO2025160184A1) goes much further, claiming the same molecule is a 'quadruple receptor agonist' at IGF-1, GLP-1, GIP and glucagon receptors. That claim is worth understanding properly, because it is the entire basis of the weight-loss story. GLP-1, GIP and glucagon receptors are class B GPCRs, the kind that normally need a thirty-plus residue peptide wrapping into the receptor's binding groove to switch on. A 154-dalton ring activating all three would be a genuinely significant pharmacological finding. No independent group has reported it. Searching PubMed for cyclic glycine-proline alongside GLP-1 returns nothing at all. | Amylin is a hormone your pancreas releases alongside insulin after meals. It acts on the brainstem to make you feel full sooner, slows stomach emptying, and curbs glucagon after eating. Zealand says amylin signaling also helps restore sensitivity to leptin, the body's long-term fullness signal. Native amylin is unusable as a drug because it clumps into fibrils and lasts minutes, so petrelintide was engineered to stay stable at neutral pH, avoid fibril formation, and last a week. That stability also means it can be co-formulated with other peptides, which is why Roche plans to combine it with its own GLP-1/GIP drug. The theory is that amylin gives more of a natural fullness feeling than GLP-1 drugs do, with fewer GI side effects; the tolerability part looks real so far, the bigger-picture claims still need phase 3. |
| Common Dosing | 120 mg daily, oral Once daily | Not publicly disclosed (once-weekly trial doses) Once weekly |
| Administration | Oral capsule or tablet, once daily | Subcutaneous injection once weekly |
| Typical Duration | 28 days in Phase 1, 13 weeks in Phase 2 | 16 weeks (phase 1b) to 42 weeks (phase 2) in completed trials |
| Best Time to Take | Consistent daily timing | Same day each week |
Possible Side Effects May vary by individual |
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| Research Summary | There are no peer-reviewed publications on NA-931. Not one. Everything in circulation is a conference abstract, and the abstracts carrying the efficacy numbers list Biomed's CEO as sole author with conflicts declared as 'None'. Two trials have completed, both run entirely in Australia: a 74-person Phase 1 (NCT06615700, completed September 2024) and a 126-person Phase 2 (NCT06564753, completed April 2025). Neither has results posted. A third trial (NCT06732245) would run in the US, Australia and New Zealand, but has not started recruiting. The reported weight loss is where this gets difficult. The same 126-person Phase 2 has been presented three times with three different numbers: 14.8 percent at ADA in June 2025, 13.8 percent at ENDO in July, and 13.8 percent with a different placebo-adjusted figure in a September press release. Enrolment is given as 125 in the abstracts against 126 on the registry. A result that moves between presentations is not yet a result. The company's website states NA-931 is in Phase 3. No Phase 3 trial for NA-931 is registered on ClinicalTrials.gov. The announcement traces to a single paid newswire release in January 2026, syndicated into around twenty local newspaper press-release sections, which reads like broad coverage but is one purchased placement. | A 16-week phase 1b trial (48 people) reported up to 8.6% mean weight loss at the highest dose versus 1.7% on placebo, with no early plateau. The phase 2 ZUPREME-1 trial (493 people with obesity or overweight, mean BMI 37) reported in March 2026 up to 10.7% mean weight loss at 42 weeks versus 1.7% on placebo. That is clearly less than semaglutide or tirzepatide produce, but tolerability stood out: no vomiting at the maximally effective dose, and side-effect dropouts (4.8%) no higher than placebo (4.9%). ZUPREME-2 (220 people with obesity and type 2 diabetes) reported in October 2026: 7.4-9.2% weight loss at 28 weeks versus 2.0% on placebo, placebo-adjusted HbA1c drops of 0.61-0.88 points, and GI dropouts of 1.9% versus 1.7%. Roche and Zealand have started phase 3a (ZUPREME-3, -4 and -5, about 7,000 people in total, including a cardiovascular-disease population). Honest take: a well-tolerated, moderate-strength drug whose real value may be as a combination partner, and the full peer-reviewed phase 2 data are still pending. |
Frequently Asked Questions: NA-931 vs Petrelintide
What is the difference between NA-931 and Petrelintide?
NA-931 is a weight loss peptide that na-931 (bioglutide) is cyclic glycine-proline, a two-amino-acid ring that occurs naturally as a breakdown product of igf-1. its developer, biomed industries, describes it as an oral once-daily agonist at four receptors at once - igf-1, glp-1, gip and glucagon - and has reported 13 to 15 percent weight loss in a 126-person phase 2 trial. those numbers have only ever appeared in conference abstracts, never in a peer-reviewed paper, and no trial results have been filed to clinicaltrials.gov. the same molecule is already sold as a consumer brain-health supplement and as a sigma-aldrich catalogue chemical, which makes it unusually cheap to source and unusually hard to verify. Petrelintide is a weight loss peptide that petrelintide is a long-acting amylin analog from zealand pharma, co-developed with roche, designed as a once-weekly injection for obesity. the pitch is gentler weight loss than glp-1 drugs but with far less nausea and vomiting. two phase 2 trials read out positively in 2026 (up to 10.7% weight loss at 42 weeks), and a roughly 7,000-person phase 3 program has started. it is not approved anywhere. The main differences lie in their mechanisms of action and clinical applications.
Which is better, NA-931 or Petrelintide?
Neither is universally "better" - the choice depends on your specific goals. NA-931 is typically used for weight loss purposes, while Petrelintide is used for weight loss. Always consult with a healthcare provider to determine which may be appropriate for your situation.
Can NA-931 and Petrelintide be used together?
Some peptide protocols combine multiple compounds for synergistic effects. However, using NA-931 and Petrelintide together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.