Drug family · 2 brands
Exenatide family — Byetta, Bydureon BCise
GLP-1 receptor agonist (synthetic exendin-4). FDA-approved since 2005. Trial weight loss range: ~4.5-5% across pivotal trials.
Quick answer
exenatide is a GLP-1 receptor agonist (synthetic exendin-4). FDA-approved brand-name medications containing exenatide: Byetta, Bydureon BCise. Trial weight loss varies from ~4.5-5% across pivotal trials. Each brand is FDA-approved for a specific indication; prescribers choose based on patient diagnosis and insurance coverage.
- Manufacturer: AstraZeneca
- FDA indications: Type 2 diabetes
- Trial weight loss: ~4.5-5%
- Lowest weight loss efficacy in GLP-1 class
- Frequency: Twice-daily (Byetta) or weekly (Bydureon BCise)
- Historical context: First GLP-1 agonist approved by FDA (2005)
Mechanism of action
Exenatide is synthetic exendin-4, originally isolated from the Gila monster lizard saliva. 53% sequence homology with human GLP-1 but resistant to DPP-4 degradation. First-generation GLP-1 agonist FDA-approved in 2005 (Byetta, twice-daily) followed by extended-release formulation (Bydureon BCise, weekly). Established efficacy for type 2 diabetes glycemic control with modest weight loss benefit.
FDA-approved brands containing exenatide
All brands share active ingredient exenatide but differ in indication, dosing, and formulation.
Alternatives outside the exenatide family
If exenatide options don't fit, these GLP-1 medications use a different active ingredient:
Common questions
Is exenatide still relevant in 2026?
Both exenatide products were discontinued in the US by AstraZeneca in October 2024 — Byetta and Bydureon BCise are no longer manufactured. Patients previously stable on exenatide have generally been transitioned to semaglutide, tirzepatide, or dulaglutide by their prescriber. Exenatide remains historically important as the first FDA-approved GLP-1 (2005).
Why was Byetta twice-daily in this weekly?
Byetta has a short 2.4-hour half-life requiring twice-daily dosing for therapeutic levels. Bydureon BCise uses microsphere encapsulation technology to slowly release exenatide over 7 days, enabling weekly dosing. Newer molecules (semaglutide, dulaglutide) achieve weekly dosing via modified molecular structure rather than delivery technology.
References
SUSTAIN-6 trial: Semaglutide and Cardiovascular Outcomes (Marso et al., NEJM)(2016)
SURPASS-2 trial: Tirzepatide vs Semaglutide in Type 2 Diabetes (Frias et al., NEJM)(2021)
LEADER trial: Liraglutide and Cardiovascular Outcomes in T2D (Marso et al., NEJM)(2016)
Glucagon-Like Peptide-1 Receptor Agonists: Mechanisms and Clinical Use (Drucker, Cell Metabolism)(2018)
Tirzepatide GIP/GLP-1 Dual Agonism: Mechanism Review (Lancet Diabetes & Endocrinology)(2021)
GLP-1 Effects on Gastric Emptying: Pharmacology Review (American J Physiology)(2020)