Exenatide

Mechanism (as reported)

Across the provided reviews, exenatide is described as mirroring GLP-1 actions: it improves glycemic control via glucose-dependent stimulation of insulin secretion, suppression of glucagon secretion, slowing of gastric emptying, and reduced appetite (and in one source, enhanced β-cell function). Exenatide is also discussed as part of GLP-1 receptor agonist mechanisms that include augmentation of insulin secretion, suppression of glucagon, deceleration of gastric emptying, and reduction in calorie intake and body weight. Sources also describe pharmacokinetic/pharmacodynamic distinctions between short-acting (exenatide b.i.d.) and long-acting GLP-1 receptor agonists, including differential effects on postprandial vs fasting glucose.

Key findings (each cites a source)

• Exenatide is described as a GLP-1–mimetic agent (first in a new class) with similar activity to naturally occurring GLP-1. [PMID 17931093, 16341288]
• Mechanistic research/reviews report that exenatide improves glycemic control through glucose-dependent stimulation of insulin secretion and suppression of glucagon secretion. [PMID 17931093, 16341288, 22945360, 26439329, 33068776]
• Mechanistic research/reviews report that exenatide slows gastric emptying and is associated with reduced appetite as part of its GLP-1-like effects. [PMID 17931093, 16341288, 22945360, 26439329, 33068776]
• GLP-1 receptor agonist reviews state that GLP-1 receptor agonists (including exenatide) can augment hyperglycemia-induced insulin secretion, suppress glucagon secretion at hyper- or euglycemia, decelerate gastric emptying, and reduce calorie intake and body weight. [PMID 33068776]
• A review reported that exenatide (short-acting) primarily lowers postprandial blood glucose levels, with gastric-emptying effects during longer-term treatment. [PMID 33068776, 22945360, 26439329]
• Phase III clinical trials discussed in the sources reported that exenatide therapy for 30 weeks significantly reduced glycated hemoglobin (HbA1c) and fasting and postprandial plasma glucose versus baseline when added to metformin and/or sulfonylureas, and reported average weight loss of ~2 kg. [PMID 17931093]
• Open-label extensions discussed in the sources reported that patients treated with exenatide for up to ~3 years sustained reductions in glycemic control achieved at 30 weeks and had progressive reductions in body weight. [PMID 17931093]
• The sources report that exenatide can be used in combination with other diabetes therapies (including thiazolidinediones) and may be an alternative to insulin for some patients requiring additional therapy. [PMID 17931093, 16341288]
• One review (on individualized treatment) describes GLP-1 receptor agonists (including exenatide) as short-acting compounds (e.g., exenatide, lixisenatide) versus long-acting compounds, and relates pharmacokinetic differences to pharmacodynamic profiles (postprandial vs fasting effects). [PMID 22945360]
• A review discussed that exenatide is generally well tolerated and that nausea is among the most commonly reported side effects; hypoglycemia is described as encountered especially when combined with sulfonylureas (as discussed in one source). [PMID 17931093, 16341288, 26439329]
• Pharmacology/pharmacokinetics information in one source reports peak plasma concentration ~2.1 hours after subcutaneous administration, a terminal half-life of 2.4 hours, and elimination predominantly by glomerular filtration followed by proteolytic degradation. [PMID 16484515]
• A pharmacology-focused source states that drug-drug interactions have been documented with digoxin, lovastatin, lisinopril, and acetaminophen. [PMID 16484515]