exenatide (ex-en-a-tide) Bydureon, Byetta

 Indications

Management of type 2 diabetes as an adjunct to diet and

exercise (not recommended as first-line therapy).

Action

Mimics the action of incretin which promotes endogenous

insulin secretion and promotes other mechanisms

of glucose-lowering. Therapeutic Effects: Improved

control of blood glucose.

Pharmacokinetics

Absorption: Well absorbed following subcutaneous

administration.

Distribution: Unknown.

Metabolism and Excretion: Excreted mostly by

glomerular filtration followed by degradation.

Half-life: Immediate-release—2.4 hr.

TIME/ACTION PROFILE (effects on postprandial

blood glucose)

ROUTE ONSET PEAK DURATION

Subcut (immediaterelease)

within 30 min 2.1 hr 8 hr

Subcut (extended-

release)

unknown 9 wk unknown

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Type 1 diabetes

or diabetic ketoacidosis; Severe renal impairment

or end-stage renal disease (CCr 30 mL/min); Severe

gastrointestinal disease; Personal or family history of

medullary thyroid carcinoma (extended-release only);

Multiple Endocrine Neoplasia syndrome type 2 (extended-

release only); OB: Has caused fetal physical defects

and neonatal death in animal studies; Lactation:

Excretion into breast milk unknown.

Use Cautiously in: History of pancreatitis; Moderate

renal impairment (CCr 30–50 mL/min); Concurrent

use of insulin (extended-release only); Pedi: Safety

not established.

Adverse Reactions/Side Effects

CV: dizziness, headache, jitteriness, weakness. GI:

PANCREATITIS, diarrhea, nausea, vomiting, dyspepsia,

gastroinestinal reflux. Endo: THYROID C-CELL TUMORS

(extended-release), hypoglycemia. GU: acute renal

failure. Derm: hyperhydrosis.Metab:pappetite,

weight loss. Misc: injection site reactions.

Interactions

Drug-Drug: Concurrent use with sulfonylureas or

insulin mayqrisk of hypoglycemia (pdose of sulfonylurea

or insulin if hypoglycemia occurs); concomitant

use of insulin with extended-release exenatide not

recommended. Concurrent use with nateglinide or repaglinide mayqrisk of hypoglycemia. Due to

slowed gastric emptying, maypabsorption of orally

administered medications, especially those requiring

rapid GI absorption or require a specific level for

efficacy; take oral anti-infectives and oral contraceptives

at least 1 hr before injecting exenatide).

Route/Dosage

Immediate Release (Byetta)

Subcut (Adults): 5 mcg within 60 min before morning

and evening meal; after 1 mo, dose may beqto 10 mcg

depending on response.

Renal Impairment

Subcut (Adults): CCr 30–50 mL/min—Use caution

whenqdose from 5 mcg to 10 mcg.

Extended Release (Bydureon)

Subcut (Adults): 2 mg every 7 days.

Availability

Solution for subcutaneous injection (Byetta): 250

mcg/mL in prefilled pen-injector that delivers either 5

mcg/dose (1.2-mL pen) or 10 mcg/dose (2.4-mL pen)

for 60 doses (30 days of twice daily dosing). Suspension

for subcutaneous injection (Bydureon): 2

mg/vial or pen.