Every drug on this site descends from exenatide. It was isolated as exendin-4 from the saliva of the Gila monster, found to activate the human GLP-1 receptor while resisting the enzyme that destroys native GLP-1 in minutes, and approved as Byetta on 28 April 2005. It is twice-daily, injected before meals, and by 2026 its manufacturer has discontinued every form of it. The entry is here because the class cannot be understood without it.
Mechanism and receptor profile
The Bydureon BCise label describes exenatide as a GLP-1 receptor agonist whose amino-acid sequence partially overlaps human GLP-1; it enhances glucose-dependent insulin secretion from the beta cell, suppresses inappropriately elevated glucagon, and slows gastric emptying. Because it is not a human sequence, a proportion of patients develop anti-exenatide antibodies, and the BCise label carries a warning about immunogenicity-associated loss of glycemic control that the human-analogue drugs do not.
FDA approvals, with dates
| Date | Product | What was approved | Record |
|---|---|---|---|
| 28 Apr 2005 | Byetta | New molecular entity, glycemic control in adults with type 2 diabetes; the first GLP-1 receptor agonist | NDA 021773, original |
| 27 Jan 2012 | Bydureon | New dosage form: 2 mg once-weekly extended-release microspheres, the first weekly GLP-1 | NDA 022200, original |
| 20 Oct 2017 | Bydureon BCise | New dosage form: 2 mg once-weekly autoinjector suspension | NDA 209210, original |
| 22 Jul 2021 | Bydureon BCise | Pediatric patients aged 10 and older with type 2 diabetes | NDA 209210, S-017 |
Drugs@FDA marks every exenatide product as discontinued. The labels were still being revised in 2025 (Byetta's is dated September 2025), which is why the adverse-reaction tables below are current.
Dosing as the labels state it
| Byetta | Bydureon BCise | |
|---|---|---|
| Dose | 5 mcg twice daily within 60 minutes before the morning and evening meals (or the two main meals, at least 6 hours apart); may increase to 10 mcg twice daily after 1 month | 2 mg once every 7 days, any time of day, with or without meals; no titration |
| Timing rule | Never after a meal | Day can change if the last dose was at least 3 days earlier |
| Missed dose | Resume with the next scheduled dose | Take when noticed if the next dose is at least 3 days away |
| Switching | Not applicable | Stop other exenatide products first; switching from Byetta may raise glucose for 2 to 4 weeks |
Pivotal trials and their numbers
| Trial | Population and duration | Result | PubMed |
|---|---|---|---|
| Exenatide with metformin (AMIGO program) | Adults with type 2 diabetes on metformin; 30 weeks | HbA1c -0.78 (10 mcg), -0.40 (5 mcg) vs +0.08 points placebo; weight -2.8 and -1.6 kg; 46% vs 13% reached HbA1c 7% or lower | 15855572 |
| DURATION-1 | Adults with type 2 diabetes, weekly against twice daily; 30 weeks | HbA1c -1.9 with 2 mg weekly vs -1.5 with 10 mcg twice daily; 77% vs 61% reached 7% or lower; similar weight loss | 18782641 |
| EXSCEL | 14,752 adults with type 2 diabetes, 73.1% with prior cardiovascular disease; median 3.2 years | Primary endpoint 11.4% vs 12.2%; hazard ratio 0.91 (0.83 to 1.00); non-inferior for safety, not superior (P = 0.06) | 28910237 |
EXSCEL is the reason no exenatide product carries a cardiovascular indication: the hazard ratio touched 1.00 at the upper bound and the superiority test missed.
Adverse reactions from the label
| Adverse reaction | Placebo % | Byetta % |
|---|---|---|
| Nausea | 18 | 44 |
| Vomiting | 4 | 13 |
| Diarrhea | 6 | 13 |
| Feeling jittery | 4 | 9 |
| Dizziness | 6 | 9 |
| Headache | 6 | 9 |
| Dyspepsia | 3 | 6 |
| Asthenia | 2 | 4 |
As monotherapy over 24 weeks (placebo n=77; Byetta n=155) nausea was 8% against 0% and vomiting 4% against 0%. With a sulfonylurea, hypoglycemia rose sharply: 35.7% on 10 mcg against 3.3% on placebo in the label's Table 1. For Bydureon BCise, the pooled 28-week trials (n=526) list injection site nodule at 10.5% and nausea at 8.2% as the only reactions above 5%; nausea and vomiting fell from 2% in the first week to 1% by week four.
Boxed warning
Byetta has no boxed warning. Bydureon and Bydureon BCise carry the class thyroid C-cell tumor warning and the contraindication for medullary thyroid carcinoma history or MEN 2. The BCise warnings also include drug-induced thrombocytopenia and serious injection-site reactions (abscess, cellulitis, necrosis), which are specific to the microsphere formulation.
Status and manufacturer
AstraZeneca holds all three applications. Drugs@FDA lists Byetta, Bydureon and Bydureon BCise as discontinued. The approvals stand; the products are not marketed.
Where next
Lixisenatide is the other exendin-based drug, still listed as marketed. The approval timeline starts with Byetta in 2005; the comparison table has a preset for the older GLP-1s.
Questions people ask
Why does exenatide have no thyroid boxed warning on Byetta but one on Bydureon?
The rodent thyroid C-cell findings that drive the class warning emerged with the long-acting agents. Byetta, the short-acting twice-daily product, was approved in 2005 without a boxed warning and still has none. Bydureon and Bydureon BCise, the once-weekly extended-release products, carry the class boxed warning.
Can I still get Byetta or Bydureon?
Drugs@FDA lists all exenatide products as discontinued as of September 2026. The approvals remain on the record and the labels remain posted, but the products are no longer marketed. Ask a pharmacist about current availability.
Sources
- Drugs@FDA: NDA 021773 Byetta (approval 2005-04-28; marketing status discontinued) Accessed September 4, 2026.
- Drugs@FDA: NDA 022200 Bydureon (approval 2012-01-27; marketing status discontinued) Accessed September 4, 2026.
- Drugs@FDA: NDA 209210 Bydureon BCise (approval 2017-10-20; supplement 17 approved 2021-07-22; marketing status discontinued) Accessed September 4, 2026.
- Byetta prescribing information, AstraZeneca, DailyMed set id 53d03c03-ebf7-418d-88a8-533eabd2ee4f Accessed September 4, 2026.
- Bydureon BCise prescribing information, FDA-approved label May 2025 (NDA 209210 s025) Accessed September 4, 2026.
- DeFronzo RA et al. Effects of exenatide on glycemic control and weight over 30 weeks in metformin-treated patients with type 2 diabetes. Diabetes Care 2005. PubMed 15855572 Accessed September 4, 2026.
- Drucker DJ et al. Exenatide once weekly versus twice daily for the treatment of type 2 diabetes (DURATION-1). Lancet 2008. PubMed 18782641 Accessed September 4, 2026.
- Holman RR et al. Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). N Engl J Med 2017. PubMed 28910237 Accessed September 4, 2026.
Canonical URL: https://formblendsglp1s.com/agents/exenatide. Written by the FormBlends editorial team. This page is educational and is not medical advice; see the medical disclaimer.