Exenatide - Revision history

MDElliottMD: Strip Category:MedCategory marker per interface-claude 2026-05-20 hygiene order: this page is a medicine, narrative, wiki-meta page, or stylesheet rather than a class-overview category, so it should not carry the MedCategory tag. Class memberships and other tags preserved.

2026-05-19T18:00:10Z

Strip Category:MedCategory marker per interface-claude 2026-05-20 hygiene order: this page is a medicine, narrative, wiki-meta page, or stylesheet rather than a class-overview category, so it should not carry the MedCategory tag. Class memberships and other tags preserved.

← Older revision		Revision as of 18:00, 19 May 2026
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	}}		}}

	~~[[Category:MedCategory]]~~
	[[Category:GLP-1 receptor agonists]]		[[Category:GLP-1 receptor agonists]]
	[[Category:Antidiabetic medicines]]		[[Category:Antidiabetic medicines]]
	[[Category:AstraZeneca medicines]]		[[Category:AstraZeneca medicines]]

MDElliottMD: Em-dash sweep: replace em-dash with comma per project rule; PendellsCorner verbatim quotes preserved.

2026-05-19T03:16:07Z

Em-dash sweep: replace em-dash with comma per project rule; PendellsCorner verbatim quotes preserved.

MDElliottMD: Migrate tags to (Phase 2 of indications-to-problems rebuild)

2026-05-17T00:11:51Z

Migrate <indication> tags to <problem> (Phase 2 of indications-to-problems rebuild)

← Older revision		Revision as of 00:11, 17 May 2026
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	* Cardiovascular outcomes: '''non-inferior''' but not superior to placebo in T2DM (EXSCEL) — the only major GLP-1 RA CVOT not to demonstrate superiority<ref name="exscel">Holman RR, Bethel MA, Mentz RJ et al. (2017). Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). ''NEJM'' 377(13):1228–39. doi:10.1056/NEJMoa1612917</ref>		* Cardiovascular outcomes: '''non-inferior''' but not superior to placebo in T2DM (EXSCEL) — the only major GLP-1 RA CVOT not to demonstrate superiority<ref name="exscel">Holman RR, Bethel MA, Mentz RJ et al. (2017). Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). ''NEJM'' 377(13):1228–39. doi:10.1056/NEJMoa1612917</ref>

	\| indications = <~~indication~~ ref="diabetes-type-2" author="MDElliottMD"/>		\| indications = <problem ref="diabetes-type-2" author="MDElliottMD"/>

	\| dosing = <titration slug="byetta-standard" author="MDElliottMD" title="Byetta — standard T2DM titration">		\| dosing = <titration slug="byetta-standard" author="MDElliottMD" title="Byetta — standard T2DM titration">

MDElliottMD: Fix Cargo VARCHAR(300) overflow: blank structure, shorten mechanism, move chemistry/mechanism prose to PK/PD

2026-05-16T23:33:10Z

Fix Cargo VARCHAR(300) overflow: blank structure, shorten mechanism, move chemistry/mechanism prose to PK/PD

← Older revision		Revision as of 23:33, 16 May 2026
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	\| generic = Exenatide		\| generic = Exenatide
	\| brand = Byetta (twice-daily), Bydureon BCise (weekly)		\| brand = Byetta (twice-daily), Bydureon BCise (weekly)
	\| structure = '''Exendin-4''' — a 39-amino-acid peptide originally isolated from the saliva of the Gila monster (''[[Heloderma suspectum]]''). Only 53% homologous with human [[GLP-1]] but naturally resistant to [[DPP-4]] cleavage because of a glycine at position 2.<ref name="eng1992">Eng J, Kleinman WA, Singh L et al. (1992). Isolation and characterization of exendin-4, an exendin-3 analogue, from ''Heloderma suspectum'' venom. ''J Biol Chem'' 267(11):7402–5.</ref>		\| structure =

	\| classes = [[GLP-1 receptor agonist]] · [[Antidiabetic medicines\|Antidiabetic]] · First-in-class incretin mimetic		\| classes = [[GLP-1 receptor agonist]] · [[Antidiabetic medicines\|Antidiabetic]] · First-in-class incretin mimetic
	\| mechanism = ~~Selective agonist~~ of the [[GLP-1 receptor]]. Mechanism identical to other GLP-1 RAs (glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression).<ref name="drucker2022">Drucker DJ (2022). GLP-~~1 physiology informs the pharmacotherapy of obesity. ''Mol Metab'' 57:101351~~.~~</ref>~~		\| mechanism = Agonist of the [[GLP-1 receptor]]; exendin-4 derivative from Gila monster venom.

	\| uses = [[Type 2 diabetes mellitus]] (adjunct, second-line)		\| uses = [[Type 2 diabetes mellitus]] (adjunct, second-line)
	\| starting_dose = Byetta: 5 µg SC twice daily, within 60 min before morning and evening meals<ref name="byetta-label">US FDA. ''Byetta (exenatide) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/021773s9s11s18s22s25lbl.pdf</ref> · Bydureon BCise: 2 mg SC once weekly<ref name="bydureon-label">US FDA. ''Bydureon BCise (exenatide extended-release) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/209210s000lbl.pdf</ref>		\| starting_dose = Byetta: 5 µg SC twice daily, within 60 min before morning and evening meals<ref name="byetta-label">US FDA. ''Byetta (exenatide) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/021773s9s11s18s22s25lbl.pdf</ref> · Bydureon BCise: 2 mg SC once weekly<ref name="bydureon-label">US FDA. ''Bydureon BCise (exenatide extended-release) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/209210s000lbl.pdf</ref>
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	In contrast to the long-acting weekly agents that followed, exenatide carries a heavier GI side-effect burden (especially Byetta BID) and is associated with anti-exenatide antibody formation in a substantial minority of users — antibodies that can reduce efficacy.<ref name="byetta-label"/> Twice-daily Byetta was discontinued in the United States in 2024.{{Citation needed}} Bydureon BCise remains available but is no longer commonly prescribed first-line.		In contrast to the long-acting weekly agents that followed, exenatide carries a heavier GI side-effect burden (especially Byetta BID) and is associated with anti-exenatide antibody formation in a substantial minority of users — antibodies that can reduce efficacy.<ref name="byetta-label"/> Twice-daily Byetta was discontinued in the United States in 2024.{{Citation needed}} Bydureon BCise remains available but is no longer commonly prescribed first-line.

	\| pharmacokinetics = '''Byetta''' (BID): rapid absorption, peak ~2.1 h, half-life ~2.4 h. Renal elimination predominates (unlike most other GLP-1 RAs); dose adjustment required for CrCl 30–50, contraindicated <30.<ref name="byetta-label"/>		\| pharmacokinetics = '''Chemistry'''. '''Exendin-4''' — a 39-amino-acid peptide originally isolated from the saliva of the Gila monster (''[[Heloderma suspectum]]''). Only 53% homologous with human [[GLP-1]] but naturally resistant to [[DPP-4]] cleavage because of a glycine at position 2.<ref name="eng1992">Eng J, Kleinman WA, Singh L et al. (1992). Isolation and characterization of exendin-4, an exendin-3 analogue, from ''Heloderma suspectum'' venom. ''J Biol Chem'' 267(11):7402–5.</ref>

			'''Byetta''' (BID): rapid absorption, peak ~2.1 h, half-life ~2.4 h. Renal elimination predominates (unlike most other GLP-1 RAs); dose adjustment required for CrCl 30–50, contraindicated <30.<ref name="byetta-label"/>

	'''Bydureon BCise''' (weekly): exenatide is encapsulated in slow-release biodegradable polymer microspheres; multiple peaks occur as successive microsphere cohorts release the peptide. Steady-state plasma levels are reached only after 6–7 weeks of weekly dosing — meaning early efficacy looks weaker than other weekly GLP-1 RAs.<ref name="bydureon-label"/>		'''Bydureon BCise''' (weekly): exenatide is encapsulated in slow-release biodegradable polymer microspheres; multiple peaks occur as successive microsphere cohorts release the peptide. Steady-state plasma levels are reached only after 6–7 weeks of weekly dosing — meaning early efficacy looks weaker than other weekly GLP-1 RAs.<ref name="bydureon-label"/>

	\| pharmacodynamics = At maintenance doses:		\| pharmacodynamics = '''Receptor pharmacology'''. Selective agonist of the [[GLP-1 receptor]]. Mechanism identical to other GLP-1 RAs (glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression).<ref name="drucker2022">Drucker DJ (2022). GLP-1 physiology informs the pharmacotherapy of obesity. ''Mol Metab'' 57:101351.</ref>

			At maintenance doses:
	* HbA1c reduction of ~0.8–1.0 percentage points (Byetta 10 µg BID or Bydureon 2 mg/wk)<ref name="byetta-label"/><ref name="bydureon-label"/>		* HbA1c reduction of ~0.8–1.0 percentage points (Byetta 10 µg BID or Bydureon 2 mg/wk)<ref name="byetta-label"/><ref name="bydureon-label"/>
	* Weight loss of ~2–3 kg<ref name="byetta-label"/>		* Weight loss of ~2–3 kg<ref name="byetta-label"/>

MDElliottMD: Create Exenatide page (initial draft, MedTemplate, full inline cites)

2026-05-16T23:11:35Z

Create Exenatide page (initial draft, MedTemplate, full inline cites)

New page

{{MedTemplate
| generic = Exenatide
| brand = Byetta (twice-daily), Bydureon BCise (weekly)
| structure = '''Exendin-4''' — a 39-amino-acid peptide originally isolated from the saliva of the Gila monster (''[[Heloderma suspectum]]''). Only 53% homologous with human [[GLP-1]] but naturally resistant to [[DPP-4]] cleavage because of a glycine at position 2.<ref name="eng1992">Eng J, Kleinman WA, Singh L et al. (1992). Isolation and characterization of exendin-4, an exendin-3 analogue, from ''Heloderma suspectum'' venom. ''J Biol Chem'' 267(11):7402–5.</ref>
| classes = [[GLP-1 receptor agonist]] · [[Antidiabetic medicines|Antidiabetic]] · First-in-class incretin mimetic
| mechanism = Selective agonist of the [[GLP-1 receptor]]. Mechanism identical to other GLP-1 RAs (glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression).<ref name="drucker2022">Drucker DJ (2022). GLP-1 physiology informs the pharmacotherapy of obesity. ''Mol Metab'' 57:101351.</ref>
| uses = [[Type 2 diabetes mellitus]] (adjunct, second-line)
| starting_dose = Byetta: 5 µg SC twice daily, within 60 min before morning and evening meals<ref name="byetta-label">US FDA. ''Byetta (exenatide) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/021773s9s11s18s22s25lbl.pdf</ref> · Bydureon BCise: 2 mg SC once weekly<ref name="bydureon-label">US FDA. ''Bydureon BCise (exenatide extended-release) prescribing information.'' AstraZeneca. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/209210s000lbl.pdf</ref>
| preparations = Byetta pre-filled multi-dose pen: 5 µg / 10 µg per dose<ref name="byetta-label"/> · Bydureon BCise single-dose autoinjector: 2 mg extended-release microsphere suspension<ref name="bydureon-label"/>
| fda_max = 10 µg twice daily (Byetta)<ref name="byetta-label"/> · 2 mg once weekly (Bydureon BCise)<ref name="bydureon-label"/>
| routes = Subcutaneous (abdomen, thigh, upper arm)<ref name="byetta-label"/>
| onset = Glycemic effect within hours (Byetta); weeks (Bydureon — extended-release microsphere)<ref name="bydureon-label"/>
| duration = ~10 hours (Byetta)<ref name="byetta-label"/> · ~7 days steady-state (Bydureon, after ~6–7 weeks of weekly dosing to reach steady state)<ref name="bydureon-label"/>
| halflife = ~2.4 hours (Byetta — short, hence the BID schedule)<ref name="byetta-label"/> · Effective release half-life ~2 weeks (Bydureon)<ref name="bydureon-label"/>
| bioavailability = SC ~65%–75%{{Citation needed}}
| pregnancy = Avoid. Discontinue before planned pregnancy.<ref name="byetta-label"/>
| legal = Rx-only;<ref name="byetta-label"/> not a controlled substance
| intro = Exenatide is the '''first-in-class''' [[GLP-1 receptor agonist]], approved by the FDA in April 2005 (Byetta, twice-daily subcutaneous)<ref name="byetta-label"/> and later as an extended-release weekly formulation (Bydureon, January 2012; reformulated as Bydureon BCise in 2017).<ref name="bydureon-label"/>

Exenatide is a synthetic version of '''exendin-4''', originally isolated by John Eng at the Bronx VA Medical Center in 1992 from the saliva of the [[Gila monster]] (''[[Heloderma suspectum]]'').<ref name="eng1992"/> The peptide is only 53% homologous to native human GLP-1 but is naturally resistant to DPP-4 — that natural resistance is what made it the first clinically usable incretin mimetic, validating the GLP-1 receptor as a therapeutic target and opening the path to all subsequent agents in the class.

In contrast to the long-acting weekly agents that followed, exenatide carries a heavier GI side-effect burden (especially Byetta BID) and is associated with anti-exenatide antibody formation in a substantial minority of users — antibodies that can reduce efficacy.<ref name="byetta-label"/> Twice-daily Byetta was discontinued in the United States in 2024.{{Citation needed}} Bydureon BCise remains available but is no longer commonly prescribed first-line.

| pharmacokinetics = '''Byetta''' (BID): rapid absorption, peak ~2.1 h, half-life ~2.4 h. Renal elimination predominates (unlike most other GLP-1 RAs); dose adjustment required for CrCl 30–50, contraindicated <30.<ref name="byetta-label"/>

'''Bydureon BCise''' (weekly): exenatide is encapsulated in slow-release biodegradable polymer microspheres; multiple peaks occur as successive microsphere cohorts release the peptide. Steady-state plasma levels are reached only after 6–7 weeks of weekly dosing — meaning early efficacy looks weaker than other weekly GLP-1 RAs.<ref name="bydureon-label"/>

| pharmacodynamics = At maintenance doses:
* HbA1c reduction of ~0.8–1.0 percentage points (Byetta 10 µg BID or Bydureon 2 mg/wk)<ref name="byetta-label"/><ref name="bydureon-label"/>
* Weight loss of ~2–3 kg<ref name="byetta-label"/>
* Cardiovascular outcomes: '''non-inferior''' but not superior to placebo in T2DM (EXSCEL) — the only major GLP-1 RA CVOT not to demonstrate superiority<ref name="exscel">Holman RR, Bethel MA, Mentz RJ et al. (2017). Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). ''NEJM'' 377(13):1228–39. doi:10.1056/NEJMoa1612917</ref>

| indications = <indication ref="diabetes-type-2" author="MDElliottMD"/>

| dosing = <titration slug="byetta-standard" author="MDElliottMD" title="Byetta — standard T2DM titration">
5 µg SC twice daily (morning and evening, within 60 min before meals) × 1 month
→ 10 µg SC twice daily (max) if tolerated and additional glycemic control needed<ref name="byetta-label"/>

'''Renal dosing''': avoid if CrCl <30 mL/min; use with caution if CrCl 30–50.<ref name="byetta-label"/>
</titration>

<titration slug="bydureon-standard" author="MDElliottMD" title="Bydureon BCise — standard T2DM dosing">
2 mg SC once weekly, same day each week, no titration required.<ref name="bydureon-label"/>

Steady-state plasma exenatide is reached only after 6–7 weeks of dosing — counsel patients that the medicine will keep ramping up well after the first injection. HbA1c response should be assessed at 12+ weeks, not earlier.<ref name="bydureon-label"/>

'''Renal dosing''': avoid if CrCl <45 mL/min.<ref name="bydureon-label"/>
</titration>

| effects = * '''Nausea''' — historically the highest of any GLP-1 RA. ~40–50% of Byetta BID users report nausea; ~20% with Bydureon weekly.<ref name="byetta-label"/><ref name="bydureon-label"/>
* '''Vomiting, diarrhea, constipation, dyspepsia'''<ref name="byetta-label"/>
* '''Injection-site reactions''' — notably higher with Bydureon (small nodules at injection sites are common, often visible/palpable for weeks)<ref name="bydureon-label"/>
* '''Anti-exenatide antibodies''' — form in ~40% of users; high titers correlate with reduced glycemic efficacy<ref name="byetta-label"/>
* '''Headache, jitteriness''' (less common){{Citation needed}}

| interactions = <pharmaInteractions/>

| pregnancy_details = Avoid. Animal embryofetal toxicity is documented.<ref name="byetta-label"/> Byetta's short half-life means rapid washout (days); Bydureon's slow microsphere release means a much longer effective washout (weeks to months).<ref name="bydureon-label"/>

| monitoring = * Baseline: HbA1c, weight, BP, renal function (especially important for exenatide — renally cleared)<ref name="byetta-label"/>
* Personal or family history of MTC or [[MEN2]] — '''contraindicated''', do not start (Bydureon only — Byetta's label predates the class boxed warning conversion)<ref name="bydureon-label"/>
* Every 3 months for first year: HbA1c, weight, GI tolerability, renal function, signs of [[pancreatitis]] or [[gallbladder disease]]
* '''Pre-procedure''': Byetta — skip the dose before the procedure; Bydureon — hold weekly dose ≥7 days pre-op<ref name="kindel2024">Kindel TL et al. (2024). Perioperative GLP-1 receptor agonist safety guidance. ''Surg Obes Relat Dis'' 20(12):1183–8.</ref>

| counseling = * Byetta: inject within 60 min ''before'' a meal (not after). Skip the dose if you skip the meal.<ref name="byetta-label"/>
* Bydureon: same day each week. Suspension must be activated by vigorous shaking until uniformly cloudy — administration immediately after mixing is required.<ref name="bydureon-label"/>
* Expect small injection-site nodules with Bydureon — these are the polymer microspheres and usually resolve over weeks to months.<ref name="bydureon-label"/>
* GI side effects with Byetta BID peak in the first 8 weeks and often improve.<ref name="byetta-label"/>
* '''Surgery''': hold Bydureon ≥7 days pre-op; for Byetta, skip the pre-procedure dose.<ref name="kindel2024"/>

| anecdotes = <vote slug="bydureon-nodules"/>

| seealso = [[GLP-1 receptor agonist]] · [[Semaglutide]] · [[Liraglutide]] · [[Dulaglutide]] · [[Tirzepatide]] · [[Gila monster]] · [[Type 2 diabetes mellitus]]

| references = <references/>
}}

[[Category:MedCategory]]
[[Category:GLP-1 receptor agonists]]
[[Category:Antidiabetic medicines]]
[[Category:AstraZeneca medicines]]

← Older revision		Revision as of 03:16, 19 May 2026
Line 12:		Line 12:
	\| fda_max = 10 µg twice daily (Byetta)<ref name="byetta-label"/> · 2 mg once weekly (Bydureon BCise)<ref name="bydureon-label"/>		\| fda_max = 10 µg twice daily (Byetta)<ref name="byetta-label"/> · 2 mg once weekly (Bydureon BCise)<ref name="bydureon-label"/>
	\| routes = Subcutaneous (abdomen, thigh, upper arm)<ref name="byetta-label"/>		\| routes = Subcutaneous (abdomen, thigh, upper arm)<ref name="byetta-label"/>
	\| onset = Glycemic effect within hours (Byetta); weeks (Bydureon — extended-release microsphere)<ref name="bydureon-label"/>		\| onset = Glycemic effect within hours (Byetta); weeks (Bydureon, extended-release microsphere)<ref name="bydureon-label"/>
	\| duration = ~10 hours (Byetta)<ref name="byetta-label"/> · ~7 days steady-state (Bydureon, after ~6–7 weeks of weekly dosing to reach steady state)<ref name="bydureon-label"/>		\| duration = ~10 hours (Byetta)<ref name="byetta-label"/> · ~7 days steady-state (Bydureon, after ~6–7 weeks of weekly dosing to reach steady state)<ref name="bydureon-label"/>
	\| halflife = ~2.4 hours (Byetta — short, hence the BID schedule)<ref name="byetta-label"/> · Effective release half-life ~2 weeks (Bydureon)<ref name="bydureon-label"/>		\| halflife = ~2.4 hours (Byetta, short, hence the BID schedule)<ref name="byetta-label"/> · Effective release half-life ~2 weeks (Bydureon)<ref name="bydureon-label"/>
	\| bioavailability = SC ~65%–75%{{Citation needed}}		\| bioavailability = SC ~65%–75%{{Citation needed}}
	\| pregnancy = Avoid. Discontinue before planned pregnancy.<ref name="byetta-label"/>		\| pregnancy = Avoid. Discontinue before planned pregnancy.<ref name="byetta-label"/>
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	\| intro = Exenatide is the '''first-in-class''' [[GLP-1 receptor agonist]], approved by the FDA in April 2005 (Byetta, twice-daily subcutaneous)<ref name="byetta-label"/> and later as an extended-release weekly formulation (Bydureon, January 2012; reformulated as Bydureon BCise in 2017).<ref name="bydureon-label"/>		\| intro = Exenatide is the '''first-in-class''' [[GLP-1 receptor agonist]], approved by the FDA in April 2005 (Byetta, twice-daily subcutaneous)<ref name="byetta-label"/> and later as an extended-release weekly formulation (Bydureon, January 2012; reformulated as Bydureon BCise in 2017).<ref name="bydureon-label"/>

	Exenatide is a synthetic version of '''exendin-4''', originally isolated by John Eng at the Bronx VA Medical Center in 1992 from the saliva of the [[Gila monster]] (''[[Heloderma suspectum]]'').<ref name="eng1992"/> The peptide is only 53% homologous to native human GLP-1 but is naturally resistant to DPP-4 — that natural resistance is what made it the first clinically usable incretin mimetic, validating the GLP-1 receptor as a therapeutic target and opening the path to all subsequent agents in the class.		Exenatide is a synthetic version of '''exendin-4''', originally isolated by John Eng at the Bronx VA Medical Center in 1992 from the saliva of the [[Gila monster]] (''[[Heloderma suspectum]]'').<ref name="eng1992"/> The peptide is only 53% homologous to native human GLP-1 but is naturally resistant to DPP-4, that natural resistance is what made it the first clinically usable incretin mimetic, validating the GLP-1 receptor as a therapeutic target and opening the path to all subsequent agents in the class.

	In contrast to the long-acting weekly agents that followed, exenatide carries a heavier GI side-effect burden (especially Byetta BID) and is associated with anti-exenatide antibody formation in a substantial minority of users — antibodies that can reduce efficacy.<ref name="byetta-label"/> Twice-daily Byetta was discontinued in the United States in 2024.{{Citation needed}} Bydureon BCise remains available but is no longer commonly prescribed first-line.		In contrast to the long-acting weekly agents that followed, exenatide carries a heavier GI side-effect burden (especially Byetta BID) and is associated with anti-exenatide antibody formation in a substantial minority of users, antibodies that can reduce efficacy.<ref name="byetta-label"/> Twice-daily Byetta was discontinued in the United States in 2024.{{Citation needed}} Bydureon BCise remains available but is no longer commonly prescribed first-line.

	\| pharmacokinetics = '''Chemistry'''. '''Exendin-4''' — a 39-amino-acid peptide originally isolated from the saliva of the Gila monster (''[[Heloderma suspectum]]''). Only 53% homologous with human [[GLP-1]] but naturally resistant to [[DPP-4]] cleavage because of a glycine at position 2.<ref name="eng1992">Eng J, Kleinman WA, Singh L et al. (1992). Isolation and characterization of exendin-4, an exendin-3 analogue, from ''Heloderma suspectum'' venom. ''J Biol Chem'' 267(11):7402–5.</ref>		\| pharmacokinetics = '''Chemistry'''. '''Exendin-4''', a 39-amino-acid peptide originally isolated from the saliva of the Gila monster (''[[Heloderma suspectum]]''). Only 53% homologous with human [[GLP-1]] but naturally resistant to [[DPP-4]] cleavage because of a glycine at position 2.<ref name="eng1992">Eng J, Kleinman WA, Singh L et al. (1992). Isolation and characterization of exendin-4, an exendin-3 analogue, from ''Heloderma suspectum'' venom. ''J Biol Chem'' 267(11):7402–5.</ref>

	'''Byetta''' (BID): rapid absorption, peak ~2.1 h, half-life ~2.4 h. Renal elimination predominates (unlike most other GLP-1 RAs); dose adjustment required for CrCl 30–50, contraindicated <30.<ref name="byetta-label"/>		'''Byetta''' (BID): rapid absorption, peak ~2.1 h, half-life ~2.4 h. Renal elimination predominates (unlike most other GLP-1 RAs); dose adjustment required for CrCl 30–50, contraindicated <30.<ref name="byetta-label"/>

	'''Bydureon BCise''' (weekly): exenatide is encapsulated in slow-release biodegradable polymer microspheres; multiple peaks occur as successive microsphere cohorts release the peptide. Steady-state plasma levels are reached only after 6–7 weeks of weekly dosing — meaning early efficacy looks weaker than other weekly GLP-1 RAs.<ref name="bydureon-label"/>		'''Bydureon BCise''' (weekly): exenatide is encapsulated in slow-release biodegradable polymer microspheres; multiple peaks occur as successive microsphere cohorts release the peptide. Steady-state plasma levels are reached only after 6–7 weeks of weekly dosing, meaning early efficacy looks weaker than other weekly GLP-1 RAs.<ref name="bydureon-label"/>

	\| pharmacodynamics = '''Receptor pharmacology'''. Selective agonist of the [[GLP-1 receptor]]. Mechanism identical to other GLP-1 RAs (glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression).<ref name="drucker2022">Drucker DJ (2022). GLP-1 physiology informs the pharmacotherapy of obesity. ''Mol Metab'' 57:101351.</ref>		\| pharmacodynamics = '''Receptor pharmacology'''. Selective agonist of the [[GLP-1 receptor]]. Mechanism identical to other GLP-1 RAs (glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression).<ref name="drucker2022">Drucker DJ (2022). GLP-1 physiology informs the pharmacotherapy of obesity. ''Mol Metab'' 57:101351.</ref>
Line 35:		Line 35:
	* HbA1c reduction of ~0.8–1.0 percentage points (Byetta 10 µg BID or Bydureon 2 mg/wk)<ref name="byetta-label"/><ref name="bydureon-label"/>		* HbA1c reduction of ~0.8–1.0 percentage points (Byetta 10 µg BID or Bydureon 2 mg/wk)<ref name="byetta-label"/><ref name="bydureon-label"/>
	* Weight loss of ~2–3 kg<ref name="byetta-label"/>		* Weight loss of ~2–3 kg<ref name="byetta-label"/>
	* Cardiovascular outcomes: '''non-inferior''' but not superior to placebo in T2DM (EXSCEL) — the only major GLP-1 RA CVOT not to demonstrate superiority<ref name="exscel">Holman RR, Bethel MA, Mentz RJ et al. (2017). Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). ''NEJM'' 377(13):1228–39. doi:10.1056/NEJMoa1612917</ref>		* Cardiovascular outcomes: '''non-inferior''' but not superior to placebo in T2DM (EXSCEL), the only major GLP-1 RA CVOT not to demonstrate superiority<ref name="exscel">Holman RR, Bethel MA, Mentz RJ et al. (2017). Effects of once-weekly exenatide on cardiovascular outcomes in type 2 diabetes (EXSCEL). ''NEJM'' 377(13):1228–39. doi:10.1056/NEJMoa1612917</ref>

	\| indications = <problem ref="diabetes-type-2" author="MDElliottMD"/>		\| indications = <problem ref="diabetes-type-2" author="MDElliottMD"/>

	\| dosing = <titration slug="byetta-standard" author="MDElliottMD" title="Byetta — standard T2DM titration">		\| dosing = <titration slug="byetta-standard" author="MDElliottMD" title="Byetta, standard T2DM titration">
	5 µg SC twice daily (morning and evening, within 60 min before meals) × 1 month		5 µg SC twice daily (morning and evening, within 60 min before meals) × 1 month
	→ 10 µg SC twice daily (max) if tolerated and additional glycemic control needed<ref name="byetta-label"/>		→ 10 µg SC twice daily (max) if tolerated and additional glycemic control needed<ref name="byetta-label"/>
Line 46:		Line 46:
	</titration>		</titration>

	<titration slug="bydureon-standard" author="MDElliottMD" title="Bydureon BCise — standard T2DM dosing">		<titration slug="bydureon-standard" author="MDElliottMD" title="Bydureon BCise, standard T2DM dosing">
	2 mg SC once weekly, same day each week, no titration required.<ref name="bydureon-label"/>		2 mg SC once weekly, same day each week, no titration required.<ref name="bydureon-label"/>

	Steady-state plasma exenatide is reached only after 6–7 weeks of dosing — counsel patients that the medicine will keep ramping up well after the first injection. HbA1c response should be assessed at 12+ weeks, not earlier.<ref name="bydureon-label"/>		Steady-state plasma exenatide is reached only after 6–7 weeks of dosing, counsel patients that the medicine will keep ramping up well after the first injection. HbA1c response should be assessed at 12+ weeks, not earlier.<ref name="bydureon-label"/>

	'''Renal dosing''': avoid if CrCl <45 mL/min.<ref name="bydureon-label"/>		'''Renal dosing''': avoid if CrCl <45 mL/min.<ref name="bydureon-label"/>
	</titration>		</titration>

	\| effects = * '''Nausea''' — historically the highest of any GLP-1 RA. ~40–50% of Byetta BID users report nausea; ~20% with Bydureon weekly.<ref name="byetta-label"/><ref name="bydureon-label"/>		\| effects = * '''Nausea''', historically the highest of any GLP-1 RA. ~40–50% of Byetta BID users report nausea; ~20% with Bydureon weekly.<ref name="byetta-label"/><ref name="bydureon-label"/>
	* '''Vomiting, diarrhea, constipation, dyspepsia'''<ref name="byetta-label"/>		* '''Vomiting, diarrhea, constipation, dyspepsia'''<ref name="byetta-label"/>
	* '''Injection-site reactions''' — notably higher with Bydureon (small nodules at injection sites are common, often visible/palpable for weeks)<ref name="bydureon-label"/>		* '''Injection-site reactions''', notably higher with Bydureon (small nodules at injection sites are common, often visible/palpable for weeks)<ref name="bydureon-label"/>
	* '''Anti-exenatide antibodies''' — form in ~40% of users; high titers correlate with reduced glycemic efficacy<ref name="byetta-label"/>		* '''Anti-exenatide antibodies''', form in ~40% of users; high titers correlate with reduced glycemic efficacy<ref name="byetta-label"/>
	* '''Headache, jitteriness''' (less common){{Citation needed}}		* '''Headache, jitteriness''' (less common){{Citation needed}}

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	\| pregnancy_details = Avoid. Animal embryofetal toxicity is documented.<ref name="byetta-label"/> Byetta's short half-life means rapid washout (days); Bydureon's slow microsphere release means a much longer effective washout (weeks to months).<ref name="bydureon-label"/>		\| pregnancy_details = Avoid. Animal embryofetal toxicity is documented.<ref name="byetta-label"/> Byetta's short half-life means rapid washout (days); Bydureon's slow microsphere release means a much longer effective washout (weeks to months).<ref name="bydureon-label"/>

	\| monitoring = * Baseline: HbA1c, weight, BP, renal function (especially important for exenatide — renally cleared)<ref name="byetta-label"/>		\| monitoring = * Baseline: HbA1c, weight, BP, renal function (especially important for exenatide, renally cleared)<ref name="byetta-label"/>
	* Personal or family history of MTC or [[MEN2]] — '''contraindicated''', do not start (Bydureon only — Byetta's label predates the class boxed warning conversion)<ref name="bydureon-label"/>		* Personal or family history of MTC or [[MEN2]], '''contraindicated''', do not start (Bydureon only, Byetta's label predates the class boxed warning conversion)<ref name="bydureon-label"/>
	* Every 3 months for first year: HbA1c, weight, GI tolerability, renal function, signs of [[pancreatitis]] or [[gallbladder disease]]		* Every 3 months for first year: HbA1c, weight, GI tolerability, renal function, signs of [[pancreatitis]] or [[gallbladder disease]]
	* '''Pre-procedure''': Byetta — skip the dose before the procedure; Bydureon — hold weekly dose ≥7 days pre-op<ref name="kindel2024">Kindel TL et al. (2024). Perioperative GLP-1 receptor agonist safety guidance. ''Surg Obes Relat Dis'' 20(12):1183–8.</ref>		* '''Pre-procedure''': Byetta, skip the dose before the procedure; Bydureon, hold weekly dose ≥7 days pre-op<ref name="kindel2024">Kindel TL et al. (2024). Perioperative GLP-1 receptor agonist safety guidance. ''Surg Obes Relat Dis'' 20(12):1183–8.</ref>

	\| counseling = * Byetta: inject within 60 min ''before'' a meal (not after). Skip the dose if you skip the meal.<ref name="byetta-label"/>		\| counseling = * Byetta: inject within 60 min ''before'' a meal (not after). Skip the dose if you skip the meal.<ref name="byetta-label"/>
	* Bydureon: same day each week. Suspension must be activated by vigorous shaking until uniformly cloudy — administration immediately after mixing is required.<ref name="bydureon-label"/>		* Bydureon: same day each week. Suspension must be activated by vigorous shaking until uniformly cloudy, administration immediately after mixing is required.<ref name="bydureon-label"/>
	* Expect small injection-site nodules with Bydureon — these are the polymer microspheres and usually resolve over weeks to months.<ref name="bydureon-label"/>		* Expect small injection-site nodules with Bydureon, these are the polymer microspheres and usually resolve over weeks to months.<ref name="bydureon-label"/>
	* GI side effects with Byetta BID peak in the first 8 weeks and often improve.<ref name="byetta-label"/>		* GI side effects with Byetta BID peak in the first 8 weeks and often improve.<ref name="byetta-label"/>
	* '''Surgery''': hold Bydureon ≥7 days pre-op; for Byetta, skip the pre-procedure dose.<ref name="kindel2024"/>		* '''Surgery''': hold Bydureon ≥7 days pre-op; for Byetta, skip the pre-procedure dose.<ref name="kindel2024"/>