Exenatide extended-release (Bydureon): A once-weekly treatment (along with diet and exercise) to improve glycemic control in adults with type 2 diabetes mellitus in multiple clinical settings

More than 25 million Americans (≥20 years of age) are thought to have type 2 diabetes mellitus (T2DM). On January 27, 2012, FDA approved exenatide extended-release (Bydureon) injectable suspension as a once weekly treatment (along with diet and exercise) to improve glycemic control in adults with T2DM in multiple clinical settings. However, it is not recommended as first-line therapy for patients inadequately controlled on diet and exercise. Exenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist, enhances glucose-dependent insulin secretion by the pancreatic beta-cell, suppresses inappropriately elevated glucagon secretion, and slows gastric emptying.

Efficacy. Bydureon's efficacy was established in a 24-week, randomized, open-label trial. The trial compared the efficacy of Bydureon (n=129) to immediate-release exenatide (Byetta) (n=123) in patients with T2DM and inadequate glycemic control. Patients were previously treated with diet and exercise alone, single oral antidiabetic therapy (metformin, a sulfonylurea, or a thiazolidinedione), or a combination of the 2 therapies. The trial's primary end point was change in HbA_1c from baseline to week 24. Bydureon produced a statistically significant reduction in HbA_1c (-0.7%; 95% CI, -0.9, -0.4) and fasting plasma glucose (-20 mg/dL, 95% CI, -31, -10) in comparison to Byetta. Moreover, a larger percentage of patients reached an HbA_1c of <7% at week 24 with Bydureon compared to Byetta (58% vs 30%, P<.001). Both drugs reduced body weight compared to baseline (-2.3 kg for Bydureon vs -1.4 kg for Byetta).

Safety. In these clinical trials, the most common adverse events (occurring in ≥5%) associated with Bydureon were nausea, diarrhea, headache, vomiting, constipation, injection-site pruritus, injection-site nodule, and dyspepsia. Bydureon may cause hypoglycemia, particularly when administered with a sulfonylurea. Bydureon may cause thyroid C-cell tumors, and therefore, is contraindicated in patients with a family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2. Bydureon may also cause pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis; alternatives should be considered in patients with a history of pancreatitis. If pancreatitis is suspected, Bydureon should be discontinued, and if confirmed, the drug should not be restarted.