Metabolic & Fat Loss FDA Approved

Exenatide

Also known as: Byetta, Bydureon, Exendin-4

Molecular Identifiers

Molecular Formula

C184H282N50O60S

CAS Number

141758-74-9

PubChem CID

45588096

Molecular Weight

4186.6 Da

Overview

GLP-1 receptor agonist derived from the saliva of the Gila monster lizard (Heloderma suspectum), composed of 39 amino acids with a molecular weight of approximately 4,186.6 Da. First GLP-1 agonist approved for clinical use, with 53% homology to human GLP-1.

FDA-approved as Byetta (2005) in daily formulation and Bydureon (2012) in weekly extended-release formulation for type 2 diabetes treatment. First GLP-1 agonist approved for clinical use.

Exenatide improves glycemic control in type 2 diabetes by stimulating glucose-dependent insulin secretion, suppressing glucagon, delaying gastric emptying, and reducing appetite. It produces modest weight loss and has a low risk of hypoglycemia as monotherapy, but gastrointestinal effects (nausea, vomiting, diarrhea) are common, especially during the first weeks.

It is currently prescribed as second-line therapy in type 2 diabetes, in two formulations: Byetta, a twice-daily subcutaneous injection given 60 minutes before main meals, and Bydureon, an extended-release microsphere suspension administered once weekly. It has been ceding ground to longer-half-life analogs (dulaglutide, semaglutide) but remains available in many markets.

Exenatide was the first approved GLP-1 agonist, derived from exendin-4 isolated in the saliva of the Heloderma suspectum lizard (Gila monster), a peptide naturally resistant to DPP-4 degradation. FDA-approved in 2005 (Byetta) and in 2012 in its weekly formulation (Bydureon).

Among GLP-1 agonists, it is the historical pioneer of the class: compared with dulaglutide and semaglutide — second-generation analogs with longer half-life, straightforward weekly dosing, and a more robust effect on weight loss and glycemic control — it now has a disadvantage in convenience and efficacy, retaining a niche in markets where modern analogs have limited access or prohibitive cost.

Sequence (1 letter): HGEGTFTSDLSKQMEEEAVRLFIEWLKNGGPSSGAPPPS
Extended notation: His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser

Half-life

~2.4 hours

Administration Route

Subcutaneous

Category

Metabolic & Fat Loss

Mechanism of Action

  • GLP-1 receptor agonism (glucose-dependent insulin secretion)
  • Suppression of glucagon secretion in hyperglycemia
  • Delayed gastric emptying
  • Appetite reduction via central signaling
  • Promotion of pancreatic beta cell proliferation and survival

Dosage Protocol

Data compiled from the literature. This does not constitute medical advice.

Parameter Value
Dose 5-10 mcg per injection (subcutaneous)
Frequency Twice daily (Byetta) or once weekly (Bydureon)
Timing 60 minutes before main meals (daily formulation)
Duration Continuous use

Reported Side Effects

Adverse effects described in the literature. Severity and frequency vary between individuals.

  • Nausea
  • Vomiting
  • Diarrhea
  • Headache
  • Dizziness
  • Hypoglycemia (with sulfonylureas)

Product Properties

Purity >98%
Appearance White lyophilized powder
Solubility Soluble in water and bacteriostatic water
Source Solid-phase peptide synthesis (SPPS) or recombinant DNA technology
Storage Lyophilized: -20°C for up to 2 years, 2-8°C for up to 6 months. Reconstituted: 2-8°C for up to 4 weeks. Protect from light and moisture. Avoid repeated freeze-thaw cycles.

Presentations & Preparation

Vials of Exenatide found in the research market:

5 mg10 mg

Reconstitution

  • Diluent: Bacteriostatic water
  • Volume: According to vial concentration
  • Slowly inject the diluent against the vial wall
  • Gently swirl until fully dissolved — never shake
  • Start with 5 mcg twice daily for 30 days before escalating to 10 mcg

Storage

  • Lyophilized: Refrigerated 2-8°C
  • Reconstituted: Refrigerated 2-8°C (up to 30 days)
  • Protect from direct light
  • Do not freeze after reconstitution
  • Pre-filled pens must be used within 30 days after first use
Reconstitution Calculator

Scientific Studies

Published studies on Exenatide.

2005 · Diabetes Care

Effects of exenatide (exendin-4) on glycemic control and weight over 30 weeks in metformin-treated patients with type 2 diabetes

DeFronzo RA, Ratner RE, Han J, Kim DD, Fineman MS, Baron AD
2004 · Diabetes Care

Effects of exenatide (exendin-4) on glycemic control over 30 weeks in sulfonylurea-treated patients with type 2 diabetes

Buse JB, Henry RR, Han J, Kim DD, Fineman MS, Baron AD

Related Peptides

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AOD 9604

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Cagrilintide

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Dulaglutide

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