Avexitide
A GLP-1 blocker in development for dangerous low blood sugar after gastric bypass
Avexitide is exendin 9-39, a peptide that blocks the GLP-1 receptor. After gastric bypass, some people develop insulin surges and severe hypoglycaemia after meals; avexitide aims to blunt those surges. Phase 3 results were reported in August 2026.
What is it?
Most peptide drugs in this encyclopedia activate the GLP-1 receptor. Avexitide blocks it. It is exendin 9-39, a shortened form of the exendin peptide that exenatide is based on; a 1998 study in healthy volunteers showed it is a potent GLP-1 antagonist with no activating effect of its own.
The problem it targets is post-bariatric hypoglycaemia. After Roux-en-Y gastric bypass, food reaches the gut quickly, GLP-1 surges and the pancreas can release far too much insulin, driving blood sugar dangerously low an hour or two after eating. In small trials, avexitide raised the lowest blood sugar after meals and cut peak insulin, and the phase 2 PREVENT trial reduced hypoglycaemic events over 28 days.
On August 18, 2026, its developer Amylyx reported that the 78-person phase 3 LUCIDITY trial met its primary end point, a 55% reduction in serious hypoglycaemic events against placebo, and that it plans to file with the FDA by the end of 2026. These are company-reported topline results, not yet a published paper; avexitide is not approved.
At a Glance
Every value in this table is printed from the Grey Peptides dataset, the same record the compound explorer and comparison tool read, so the three can never disagree.
Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Published Research
The studies behind avexitide, read from their PubMed abstracts.
A pure GLP-1 blocker in humans
In six healthy volunteers, exendin 9-39 blocked the insulin-raising effect of physiological GLP-1 and fully antagonised its suppression of glucagon, without any agonist effect, and did not alter insulin release by GIP.
First doses after gastric bypass
In nine women with post-bariatric hypoglycaemia, single injections raised the lowest glucose after a glucose drink by 66% on average, cut peak insulin by 57% and reduced neuroglycopenic symptoms by 80%, with no treatment-emergent adverse events.
Repeat dosing for three days
In 19 women, twice-daily injections reduced hypoglycaemia at every dose; at 30 mg twice daily of a liquid form, no one needed rescue glucose, the glucose nadir rose 47% and peak insulin fell 67%.
PREVENT phase 2 crossover
In 18 women, 30 mg twice daily and 60 mg once daily raised the glucose nadir by 21% and 26% and cut peak insulin by 23% and 21% against placebo, with significant falls in level 1 to 3 hypoglycaemia over 28 days and no increase in adverse events.
Children with congenital hyperinsulinism
In 16 children, infusions raised fasting glucose and cut the likelihood of hypoglycaemia by 76% to 84% at the two higher doses, and by 82% during a protein challenge.
Side Effects & Contraindications
Reported Side Effects
From the studies above.
Contraindications & Cautions
Avexitide has no label yet. Points from the research.
Legal Status
Avexitide is investigational.
Frequently Asked Questions
?What is avexitide?
Exendin 9-39, a peptide that blocks the GLP-1 receptor, in development by Amylyx for severe low blood sugar after gastric bypass surgery.
?Did avexitide work in phase 3?
Amylyx reported in August 2026 that LUCIDITY met its primary end point, with 55% fewer serious hypoglycaemic events than placebo in 78 participants. The full results have not yet been published.
?Is avexitide approved?
No. As of October 2, 2026 it is investigational; the company plans to file with the FDA by the end of 2026.
References
- [fda] US FDA, Drugs@FDA (openFDA): no application for avexitide. Read October 2, 2026.
- [press] Amylyx Pharmaceuticals. Positive topline results from the phase 3 LUCIDITY trial of avexitide in post-bariatric hypoglycemia (press release, August 18, 2026); read October 2, 2026.
- [clinical-trial] Schirra J, et al. "Exendin(9-39)amide is an antagonist of glucagon-like peptide-1(7-36)amide in humans." J Clin Invest, 1998;101(7):1421-30. PMID: 9525985.
- [clinical-trial] Craig CM, et al. "Efficacy and pharmacokinetics of subcutaneous exendin (9-39) in patients with post-bariatric hypoglycaemia." Diabetes Obes Metab, 2018;20(2):352-361. PMID: 28776922.
- [pubmed] Tan M, et al. "Safety, efficacy and pharmacokinetics of repeat subcutaneous dosing of avexitide (exendin 9-39) for treatment of post-bariatric hypoglycaemia." Diabetes Obes Metab, 2020;22(8):1406-1416. PMID: 32250530.
- [clinical-trial] Craig CM, et al. "PREVENT: A Randomized, Placebo-controlled Crossover Trial of Avexitide for Treatment of Postbariatric Hypoglycemia." J Clin Endocrinol Metab, 2021;106(8):e3235-e3248. PMID: 33616643.
- [pubmed] Stefanovski D, et al. "Exendin-(9-39) Effects on Glucose and Insulin in Children With Congenital Hyperinsulinism During Fasting and During a Meal and a Protein Challenge." Diabetes Care, 2022;45(6):1381-1390. PMID: 35416981.
Sources & Citations
Studies were read from their PubMed records; the phase 3 result is the developer's topline announcement, read October 2, 2026.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Consult a licensed healthcare provider before making health decisions.