Effect of exenatide on heart rate and blood pressure in subjects with type 2 diabetes mellitus: a double-blind, placebo-controlled, randomized pilot study.

BACKGROUND: Cardiovascular effects of glucose-lowering agents are of increasing interest. Our aim was to assess the effects of the glucagon-like peptide-1 receptor agonist exenatide on heart rate (HR) and blood pressure (BP) in subjects with type 2 diabetes mellitus (T2DM). METHODS: In this double-blind, placebo-controlled trial, subjects with T2DM on metformin and/or a thiazolidinedione were randomized to receive exenatide (5 microg for 4 weeks followed by 10 microg) or placebo BID for 12 weeks. Heart rate and BP were assessed with 24-hour ambulatory BP monitoring. The primary measure was change from baseline in mean 24-hour HR. RESULTS: Fifty-four subjects (28 exenatide, 26 placebo) were randomized and comprised the intent-to-treat population. Baseline values (exenatide and placebo) were (mean +/- SE) 74.4 +/- 2.1 and 74.5 +/- 1.9 beats/minute for HR, 126.4 +/- 3.2 and 119.9 +/- 2.8 mm Hg for systolic BP (SBP), and 75.2 +/- 2.1 and 70.5 +/- 2.0 mm Hg for diastolic BP (DBP). At 12 weeks, no significant change from baseline in 24-hour HR was observed with exenatide or placebo (LS mean +/- SE, 2.1 +/- 1.4 versus -0.7 +/- 1.4 beats/minute, respectively; between treatments, p = 0.16). Exenatide therapy was associated with trends toward lower 24-hour, daytime, and nighttime SBP; changes in DBP were similar between groups. No changes in daytime or nighttime rate pressure product were observed. With exenatide, body weight decreased from baseline by -1.8 +/- 0.4 kg (p < 0.0001; treatment difference -1.5 +/- 0.6 kg, p < 0.05). The most frequently reported adverse event with exenatide was mild to moderate nausea. CONCLUSIONS: Exenatide demonstrated no clinically meaningful effects on HR over 12 weeks of treatment in subjects with T2DM. The observed trends toward lower SBP with exenatide warrant future investigation. TRIAL REGISTRATION: NCT00516074.

Tolerability and efficacy of exenatide and titrated insulin glargine in adult patients with type 2 diabetes previously uncontrolled with metformin or a sulfonylurea: a multinational, randomized, open-label, two-period, crossover noninferiority trial.

OBJECTIVE: This study was conducted to compare the efficacy and safety profiles of exenatide and insulin glargine therapy in patients with type 2 diabetes who had not achieved glucose control with metformin or sulfonylurea monotherapy. METHODS: This multinational, randomized, open-label, crossover noninferiority study compared the efficacy of exenatide 10 pg BID and insulin glargine QD (titrated targeting a fasting serum glucose (FSG) level < or =5.6 mmol/L) in patients with type 2 diabetes treated with a single oral antidiabetic agent. The study included two 16-week treatment periods. The primary a priori outcome variable was the change in glycosylated hemoglobin (HbA(lc)). Secondary outcomes included the proportion of patients achieving the American Diabetes Association (ADA) target HbA(lc) of < or =7% and the European Association for the Study of Diabetes target of < or =6.5%, the change in FSG, end-point values and change in the 7-point self-monitored glucose profile, and change in body weight. Adverse events were assessed based on standard laboratory tests and patient reports. RESULTS: One hundred thirty-eight patients were randomized to study treatment (52.9% female, 47.1% male; 79.7% white; mean [SEM] age, 54.9 [0.8] years; duration of diabetes, 7.4 [0.4] years; body mass index, 31.1 [0.4] kg/m(2); weight, 84.8 [1.4] kg) while continuing to receive metformin (55.1%) or a sulfonylurea (44.9%). The population had a baseline least squares (LS) mean (SEM) HbA(lc) of 8.95% (0.09%) and an LS mean FSG concentration of 12.0 (0.3) mmol/L. Both exenatide and titrated insulin glargine therapy were associated with similar significant changes from baseline in HbA(1c) (both, -1.36% [0.09%]; P < 0.001); the difference between groups was not statistically significant. The LS mean HbA(1c) at end point was above the ADA target with both treatments (exenatide, 7.57% [0.09%]; insulin glargine, 7.58% [0.09%]). Similar proportions of patients achieved an HbA(1c) < or =7% (37.5% and 39.8%, respectively; P = NS) or < or =6.5% (21.5% and 13.6%). Patients lost weight during exenatide treatment, whereas they gained weight during insulin glargine treatment; the between-group difference in weight change was statistically significant (LS mean difference, -2.2 [0.3] kg; 95% CI, -2.8 to-1.7; P < 0.001). Both exenatide and insulin glargine were associated with significant reductions from baseline in FSG (-2.9 [0.2] and -4.1 [0.2] mmol/L, respectively; both, P < 0.001), although the reduction was significantly greater with insulin glargine compared with exenatide (LS mean difference, 1.2 [0.3] mmol/L; 95% CI, 0.7 to 1.7; P < 0.001). Compared with insulin glargine, exenatide was associated with significantly lower 2-hour postprandial glucose (PPG) excursions (P < 0.016) and total daily mean glucose excursion (P < 0.001). The proportions of patients reporting nausea during exenatide and insulin glargine treatment were 42.6% and 3.1%, respectively; the proportions reporting vomiting were 9.6% and 3.1%. The incidence of hypoglycemia in the 2 groups was 14.7% and 25.2% (P = NS). CONCLUSIONS: In this open-label, crossover study, treatment with exenatide or insulin glargine for 16 weeks was associated with similar significant improvements from baseline in HbA(1c), independent of treatment order. The improvements in HbA(1c) from baseline did not differ significantly between treatment groups. Exenatide therapy was associated with significant reductions in body weight and PPG excursions compared with insulin glargine, whereas insulin glargine was associated with a significantly greater reduction in FSG compared with exenatide. These findings provide additional information to guide treatment decisions in patients with type 2 diabetes who are potential candidates for either therapy.

The effect of exenatide re-exposure on safety and efficacy.

Exenatide, a synthetic peptide originally isolated from salivary secretions of Heloderma suspectum, like other subcutaneously injected peptides, can cause antibody formation. Despite that antibody formation has been observed in some patients, results from previous clinical trials have not shown safety and efficacy concerns in exenatide-naïve patients. The objective of this multicenter, open-label study was to investigate the response of anti-exenatide antibody formation and the incidence of immune-related and hypersensitivity reactions after exenatide re-exposure. Fifty-eight patients (57% male; 59+/-10 years; weight 85+/-19kg; HbA1c 8.1+/-0.9%; duration of diabetes 10+/-5 years) were enrolled. At study initiation, 98.3% of patients were taking 1 or more antidiabetes drugs, including oral medication and various types of insulin. Treatment-emergent adverse events (TEAEs) at any time during the study were observed in 40 and 47% of patients with positive and negative treatment-emergent antibodies, respectively. Immune-related AEs were observed in 6 patients (4 were antibody positive). These AEs had not been reported in their previous exposure to exenatide. Re-exposure to exenatide did not result in increased hypersensitivity reactions. Overall, 72% of patients had a baseline to endpoint reduction in HbA1c (range -0.1 to -2.8%), and 87% of antibody negative versus 62% of antibody positive patients had an HbA1c endpoint reduction. The study design and the patients' baseline characteristics, including diabetes treatment at study initiation, are confounding factors limiting clinical conclusions on exenatide's glycemic effect in this patient population. The study results indicate that anti-exenatide antibody formation did not increase the incidence of TEAEs in patients re-exposed to exenatide.