Clinical Pharmacology for Bydureon
Mechanism Of Action
Incretins, such as GLP-1, enhance glucose-dependent insulin secretion and exhibit other antihyperglycemic actions following their release into the circulation from the gut. BYDUREON is a GLP-1 receptor agonist that enhances glucose-dependent insulin secretion by the pancreatic beta-cell, suppresses inappropriately elevated glucagon secretion, and slows gastric emptying.
The amino acid sequence of exenatide partially overlaps that of human GLP-1. Exenatide is a GLP-1 receptor agonist that has been shown to bind and activate the human GLP-1 receptor in vitro. This leads to an increase in both glucose-dependent synthesis of insulin and in vivo secretion of insulin from pancreatic beta cells, by mechanisms involving cyclic AMP and/or other intracellular signaling pathways. Exenatide promotes insulin release from pancreatic beta-cells in the presence of elevated glucose concentrations.
Pharmacodynamics
Exenatide improves glycemic control through the actions described below.
Glucose-Dependent Insulin Secretion
The effect of exenatide infusion on glucose-dependent insulin secretion rates (ISR) was investigated in 11 healthy subjects. In these healthy subjects, on average, the ISR response was glucose-dependent (Figure 1). Exenatide did not impair the normal glucagon response to hypoglycemia.
Figure 1: Mean (SE) Insulin Secretion Rates During Infusion of Exenatide or Placebo by Treatment, Time, and Glycemic Condition in Healthy Subjects
SE = standard error.
Notes: 5 mmol = 90 mg/dL, 4 mmol/L = 72 mg/dL, 3.2 mmol/L = 58 mg/dL; Study medication infusion was started at time = 0 minutes.
Statistical assessments were for the last 30 minutes of each glycemic step, during which the target glucose concentrations were maintained.
*p <0.05, exenatide treatment relative to placebo.
Glucagon Secretion
In patients with type 2 diabetes, exenatide moderates glucagon secretion and lowers serum glucagon concentrations during periods of hyperglycemia.
Gastric Emptying
Exenatide slows gastric emptying, thereby reducing the rate at which postprandial glucose appears in the circulation.
Fasting And Postprandial Glucose
In a clinical study in adults with type 2 diabetes mellitus, treatment with once weekly BYDUREON resulted in mean reductions in fasting plasma glucose of -45 mg/dL and 2-hour PPG concentrations of -95 mg/dL.
Cardiac Electrophysiology
The effect of exenatide at therapeutic (253 pg/mL) and supratherapeutic (627 pg/mL) concentrations, following an intravenous infusion on QTc interval was evaluated in a randomized, placebo- and active-controlled (moxifloxacin 400 mg) three-period crossover thorough QT study in 74 healthy subjects. The upper bound of the one-sided 95% confidence interval for the largest placebo adjusted, baseline-corrected QTc based on population correction method (QTcP) was below 10 ms. Therefore, exenatide was not associated with prolongation of the QTc interval at therapeutic and supratherapeutic concentrations.
Pharmacokinetics
Absorption
Following a single dose of BYDUREON, exenatide is released from the microspheres over approximately 10 weeks. There is an initial period of release of surface-bound exenatide followed by a gradual release of exenatide from the microspheres, which results in two subsequent peaks of exenatide in plasma at around Week 2 and Week 6 to 7, respectively, representing the hydration and erosion of the microspheres.
Following initiation of once every 7 days (weekly) administration of 2 mg BYDUREON, a gradual increase in the plasma exenatide concentration is observed over 6 to 7 weeks. After 6 to 7 weeks, mean exenatide concentrations of approximately 300 pg/mL were maintained over once every 7 days (weekly) dosing intervals indicating that steady state was achieved.
Distribution
The mean apparent volume of distribution of exenatide following subcutaneous administration of a single dose of BYETTA is 28.3 L and is expected to remain unchanged for BYDUREON.
Metabolism
Elimination
Nonclinical studies have shown that exenatide is predominantly eliminated by glomerular filtration with subsequent proteolytic degradation. The mean apparent clearance of exenatide in humans is 9.1 L/hour and is independent of the dose. Approximately 10 weeks after discontinuation of BYDUREON therapy, plasma exenatide concentrations generally fall below the minimal detectable concentration of 10 pg/mL.
Specific Populations
Patients With Renal Impairment
BYDUREON has not been studied in patients with severe renal impairment (creatinine clearance <30 mL/min) or end-stage renal disease receiving dialysis. Population pharmacokinetic analysis of renally impaired patients receiving 2 mg BYDUREON indicate that there is a 62% and 33% increase in exposure in moderate (N=10) and mild (N=56) renally impaired patients, respectively, as compared to patients with normal renal function (N=84).
In a study of BYETTA in subjects with end-stage renal disease receiving dialysis, mean exenatide exposure increased by 3.4-fold compared to that of subjects with normal renal function [see Use In Specific Populations].
Patients With Hepatic Impairment
BYDUREON has not been studied in patients with acute or chronic hepatic impairment.
Age, Male And Female Patients, Race, Or Ethnic Groups, And Body Weight
Age, gender, race and body weight did not alter the pharmacokinetics of BYDUREON in population pharmacokinetic analyses.
Pediatric Patients
The clinical pharmacology of BYDUREON has been evaluated in the population pharmacokinetic study in adolescent patients with type 2 diabetes mellitus between age 11 and age less than 18 years old. The pharmacokinetic profile of BYDUREON in the pediatric population was consistent with that of the adults.
Drug Interaction Studies
Acetaminophen
When 1000 mg acetaminophen tablets were administered, either with or without a meal, following 14 weeks of BYDUREON therapy (2 mg weekly), no significant changes in acetaminophen AUC were observed compared to the control period. Acetaminophen Cmax decreased by 16% (fasting) and 5% (fed) and Tmax was increased from approximately 1 hour in the control period to 1.4 hours (fasting) and 1.3 hours (fed).
The following drug interactions have been studied using BYETTA. The potential for drug-drug interaction with BYDUREON is expected to be similar to that of BYETTA.
Warfarin
Administration of warfarin (25 mg) 35 minutes after repeated doses of BYETTA (5 mcg twice daily on days 1-2 and 10 mcg twice daily on days 3-9) in healthy volunteers delayed warfarin Tmax by approximately 2 hours. No clinically relevant effects on Cmax or AUC of S-and R-enantiomers of warfarin were observed. BYETTA did not significantly alter the pharmacodynamic properties (e.g., international normalized ratio) of warfarin [see DRUG INTERACTIONS].
Digoxin
Administration of repeated doses of BYETTA 30 minutes before oral digoxin (0.25 mg once daily) decreased the Cmax of digoxin by 17% and delayed the Tmax of digoxin by approximately 2.5 hours; however, the overall steady-state pharmacokinetic exposure (e.g., AUC) of digoxin was not changed.
Lovastatin
Administration of BYETTA (10 mcg twice daily) 30 minutes before a single oral dose of lovastatin (40 mg) decreased the AUC and Cmax of lovastatin by approximately 40% and 28%, respectively, and delayed the Tmax by about 4 hours compared with lovastatin administered alone. In the 30-week controlled clinical trials of BYETTA, the use of BYETTA in patients already receiving HMG CoA reductase inhibitors was not associated with consistent changes in lipid profiles compared to baseline.
Lisinopril
In patients with mild to moderate hypertension stabilized on lisinopril (5-20 mg/day), BYETTA (10 mcg twice daily) did not alter steady-state Cmax or AUC of lisinopril. Lisinopril steady-state Tmax was delayed by 2 hours. There were no changes in 24-hour mean systolic and diastolic blood pressure.
Oral Contraceptives
The effect of BYETTA (10 mcg twice daily) on single and on multiple doses of a combination oral contraceptive (30 mcg ethinyl estradiol plus 150 mcg levonorgestrel) was studied in healthy female subjects. Repeated daily doses of the oral contraceptive (OC) given 30 minutes after BYETTA administration decreased the Cmax of ethinyl estradiol and levonorgestrel by 45% and 27%, respectively, and delayed the Tmax of ethinyl estradiol and levonorgestrel by 3.0 hours and 3.5 hours, respectively, as compared to the oral contraceptive administered alone. Administration of repeated daily doses of the OC one hour prior to BYETTA administration decreased the mean Cmax of ethinyl estradiol by 15%, but the mean Cmax of levonorgestrel was not significantly changed as compared to when the OC was given alone. BYETTA did not alter the mean trough concentrations of levonorgestrel after repeated daily dosing of the oral contraceptive for both regimens. However, the mean trough concentration of ethinyl estradiol was increased by 20% when the OC was administered 30 minutes after BYETTA administration injection as compared to when the OC was given alone. The effect of BYETTA on OC pharmacokinetics is confounded by the possible food effect on OC in this study [see DRUG INTERACTIONS].
Immunogenicity
The observed incidence of anti-drug antibodies is highly dependent on the sensitivity and specificity of the assay. Differences in assay methods preclude meaningful comparisons of the incidence of anti-drug antibodies in the studies described below with the incidence of anti-drug antibodies in other studies, including those of BYDUREON or of other exenatide products.
Immunogenicity In Adult Patients
Anti-exenatide antibodies were measured at prespecified intervals (4-14 weeks) in BYDUREON-treated
adult patients (N=918) in five active-controlled trials for the improvement of glycemic control in adults
with type 2 diabetes mellitus (Trials 1, 2, 3, 4 and 9) [see Clinical Studies and ADVERSE REACTIONS]Â. In these five trials, 107/918 (12%) of BYDUREON-treated patients had high titer anti -exenatide antibodies (high titer was defined as ≥625) at endpoint. These patients had a lower glycemic response compared to BYDUREON-treated patients who did not have anti-exenatide antibodies at endpoint [see WARNINGS AND PRECAUTIONS].
In a 30-week, randomized, open-label, controlled trial in adults with type 2 diabetes mellitus [see ADVERSE REACTIONS], anti-exenatide antibody assessments were performed at baseline and at 4-week intervals from Week 6 to Week 30. The mean anti-exenatide antibody titer in the BYDUREON-treated patients peaked at Week 6.
Injection site reactions for BYDUREON-treated patients were more commonly observed in those who were antibody-positive (anti-exenatide antibodies) compared with those who were antibody-negative, with a greater incidence in those with higher titer anti-exenatide antibodies (defined as ≥625) [see ADVERSE REACTIONS]. There is insufficient data to assess whether the observed anti-exenatide antibodies in adults had an effect on the severity of injection site reactions, or on the incidence or severity of hypersensitivity reactions.
A total of 32 adult patients with anti-exenatide antibodies in BYDUREON Trial 9 were tested for the presence of cross-reactive antibodies to GLP-1 and/or glucagon and no treatment-emergent cross-reactive antibodies were observed.
Immunogenicity In Pediatric Patients
In a 52-week trial (24-week controlled and 28-week extended treatment period) for the improvement of glycemic control in pediatric patients with type 2 diabetes mellitus (Trial 8) [see Clinical Studies], 37/58 (64%) of BYDUREON-treated patients had high titer anti-exenatide antibodies (high titer was defined as ≥625) at any time during the study. In this trial, 60% of these patients had a peak high-titers at approximately Week 12. BYDUREON-treated pediatric patients that had high titer anti-exenatide antibodies appeared to have had a lower glycemic response compared to BYDUREON-treated pediatric patients who did not have anti-exenatide antibodies during this trial [see WARNINGS AND PRECAUTIONS].
There is insufficient data to assess whether the observed anti-exenatide antibodies in pediatric patients had an effect on the incidence or severity of hypersensitivity reactions or injection site reactions.
The potential for development of antibodies cross-reactive with endogenous GLP-1 and glucagon has not been evaluated in BYDUREON-treated pediatric patients.
Anti-Drug Antibody Effects On Pharmacokinetics In Adult And Pediatric Patients
The percentage of exenatide-treated adult and pediatric patients (age ≥11 years) with high anti-exenatide antibody titers (≥625) that had steady state exenatide plasma concentrations below limit of quantitation was higher than in those with low anti-exenatide antibody titers (<625).
Clinical Studies
Overview Of Clinical Trials
BYDUREON has been studied in adult patients with type 2 diabetes mellitus as monotherapy and in combination with metformin, a sulfonylurea, a thiazolidinedione, a combination of metformin and a sulfonylurea, a combination of metformin and a thiazolidinedione, in combination with a sodium-glucose cotransporter-2 (SGLT2) inhibitor on a background of metformin, and in combination with basal insulin [see Clinical Studies].
Cardiovascular (CV) outcomes were studied in the EXSCEL trial that enrolled adult patients with type 2 diabetes mellitus and multiple risk factors for CV disease or established CV disease [see Clinical Studies].
BYDUREON has been studied in pediatric patients aged 10 years and older with type 2 diabetes mellitus as monotherapy and in combination with metformin, a sulfonylurea, and in combination with basal insulin with or without metformin [see Clinical Studies].
Glycemic Control Trials In Adults With Type 2 Diabetes Mellitus -Monotherapy
BYDUREON Monotherapy versus Metformin, Sitagliptin, and Pioglitazone
A 26-week, randomized, comparator-controlled trial was conducted to compare the safety and efficacy of BYDUREON to metformin, sitagliptin, and pioglitazone in adult patients with type 2 diabetes whose glycemic control was inadequate with diet and exercise (Trial 1 -NCT00676338). Patients were randomly assigned to receive BYDUREON 2 mg given subcutaneously once every seven days (weekly), titrated metformin from 1000 to 2500 mg/day, sitagliptin 100 mg/day or titrated pioglitazone from 30 to 45 mg/day, all dosed according to approved labeling.
A total of 820 patients were studied: 552 (67%) were White, 102 (12%) were East Asian, 71 (9%) were West Asian, 65 (8%) were Hispanic or Latino, 25 (3.0%) were Black of African American, 4 (0.5%) were of Native American ethnicity, and 1 was classified otherwise. The mean baseline HbA1c was 8.5%.
The primary endpoint was change in HbA1c from baseline to Week 26 (or the last value at time of early discontinuation).
Efficacy Results
Treatment with BYDUREON 2 mg once weekly (QW) resulted in mean HbA1c reduction that was statistically significantly greater compared to sitagliptin 100 mg/day. The mean reduction in HbA1c was non-inferior compared with metformin 1000-2500 mg/day (mean dose 2077 mg/day at study endpoint). Non-inferiority of BYDUREON 2 mg QW to pioglitazone 30-45 mg/day (mean dose 40 mg/day at study endpoint) in reducing HbA1c after 26 weeks of treatment was not demonstrated (the mean change from baseline in HbA1c after 26 weeks was -1.6% with BYDUREON and -1.7% with pioglitazone). The non-inferiority margin was set at +0.3% in this study. The results for the primary endpoint at 26 weeks are summarized in Table 5.
The proportion of patients with a Week 26 value achieving HbA1c of less than 7% at Week 26 were 56%, 52%, 40%, and 55% for BYDUREON, metformin, sitagliptin, and pioglitazone, respectively. Patients who did achieve HbA1c goal <7% and discontinued before Week 26 were not included as responders. The mean changes from baseline to Week 26 for fasting serum glucose were -41 mg/dL, -36 mg/dL, -20 mg/dL, and -46 mg/dL, and for body weight were -2.0 kg, -2.0 kg, -0.8 kg, and +1.5 kg for BYDUREON, metformin, sitagliptin, and pioglitazone, respectively.
Table 5: Results of 26-Week Trial of BYDUREON Monotherapy versus Metformin, Sitagliptin, and Pioglitazone in Patients with Type 2 Diabetes Mellitus (Trial 1)
|
BYDUREON 2 mg QW |
Metformin 1000-2500 (mean dose 2077) mg/day |
Sitagliptin 100 mg/day |
Pioglitazone 30-45 (mean dose 40) mg/day |
| Intent-to-Treat Population (N) |
248 |
246 |
163 |
163 |
| HbA1c (%) |
| Mean Baseline |
8.4 |
8.6 |
8.4 |
8.5 |
| Mean Change at Week 26* |
-1.6 |
-1.5 |
-1.2 |
-1.7 |
| Difference from metformin* [Bonferroni-adjusted 98.3% CI| |
-0.05
[-0.26, 0.171 |
|
|
|
| Difference from sitagliptin* [Bonferroni-adjusted 98.3% CI| |
-0.39†
[-0.63, -0.161 |
|
|
|
| Difference from pioglitazone* [Bonferroni-adjusted 98.3% CI| |
0.16
[-0.08, 0.411 |
|
|
|
N = number of patients in each treatment group; mean change is least squares mean change; QW = once weekly.
The primary efficacy analysis was adjusted for multiple comparisons and a two-sided 98.3% confidence interval was utilized to assess difference between treatments. HbA1c change data at 26 weeks were available from 86%, 87%, 85%, and 82% of the randomized subjects in the BYDUREON, metformin, sitagliptin, and pioglitazone groups, respectively.
* Least squares means were obtained using a mixed model repeated measure analysis with treatment, pooled country, visit, baseline HbA1c value, and treatment by visit interaction as fixed effects, and subject as a random effect.
† p<0.001, treatment vs comparator. |
Glycemic Control Trials In Adults With Type 2 Diabetes Mellitus -Combination Therapy
BYDUREON Versus Sitagliptin And Pioglitazone, All As Add-On To Metformin Therapy
A 26-week double-blind comparator-controlled trial was conducted to compare the safety and efficacy of BYDUREON to sitagliptin and pioglitazone in patients with type 2 diabetes whose glycemic control was inadequate with metformin therapy (Trial 2 -NCT00637273). Patients were randomly assigned to receive BYDUREON 2 mg given subcutaneously once every 7 days (weekly), sitagliptin 100 mg/day or pioglitazone 45 mg/day, in addition to their existing metformin therapy.
A total of 491 patients were studied 168 (34.2%) were White, 143 (29.1%) were Hispanic or Latino, 119 (24.2%) were Asian, 52 (10.6%) were Black or African American, 3 (0.6%) were of Native American ethnicity, and 6 (1.2%) were classified otherwise. The mean baseline HbA1c was 8.5%.
The primary endpoint was change in HbA1c from baseline to Week 26 (or the last value at time of early discontinuation).
Efficacy Results
In this study, treatment with BYDUREON 2 mg QW resulted in a statistically significant mean HbA1c reduction compared to sitagliptin 100 mg/day. There was a numerically greater reduction in HbA1c with BYDUREON compared to pioglitazone, but there was not sufficient evidence to conclude superiority of BYDUREON 2 mg QW to pioglitazone 45 mg/day in reducing HbA1c after 26 weeks of treatment. Results for the primary endpoint at 26 weeks are summarized in Table 6.
The proportion of patients with a Week 26 value achieving HbA1c of less than 7% at Week 26 were 46%, 30%, and 39% for BYDUREON, sitagliptin, and pioglitazone, respectively. Patients who did achieve an HbA1c goal <7% and discontinued before Week 26 were not included as responders. The mean changes from baseline to Week 26 for fasting serum glucose were -32 mg/dL, -16 mg/dL and -27 mg/dL, and for body weight were -2.3 kg, -0.8 kg and +2.8 kg for BYDUREON, sitagliptin, and pioglitazone, respectively.
Table 6: Results of 26-Week Trial of BYDUREON versus Sitagliptin and Pioglitazone, All as Add-On to Metformin Therapy in Patients with Type 2 Diabetes Mellitus (Trial 2)
|
BYDUREON 2 mg QW |
Sitagliptin 100 mg/day |
Pioglitazone 45 mg/day |
| Intent-to-Treat Population (N) |
160 |
166 |
165 |
| HbA1c (%) |
| Mean Baseline |
8.6 |
8.5 |
8.5 |
| Mean Change at Week 26* |
-1.5 |
-0.9 |
-1.2 |
| Difference from sitagliptin* [95% CI] |
-0.63
[-0.89, -0.37] |
|
|
| Difference from pioglitazone* [95% CI] |
-0.32
[-0.57, -0.06] |
|
|
N = number of patients in each treatment group; mean change is least squares mean change; QW = once weekly.
* Least squares means were obtained using an ANCOVA model with treatment, baseline HbA1c stratum, and country as fixed effects. Missing Week 26 data (28%, 18%, and 24% for the BYDUREON, sitagliptin, and pioglitazone groups, respectively) were imputed by the LOCF technique. |
BYDUREON Versus Insulin Glargine, Both As Add-On To Metformin Or Metformin + Sulfonylurea Therapy
A 26-week open-label comparator-controlled trial was conducted to compare the safety and efficacy of BYDUREON to titrated insulin glargine in patients with type 2 diabetes whose glycemic control was inadequate with metformin or metformin plus sulfonylurea therapy (Trial 3 -NCT00641056). Patients were randomly assigned to receive BYDUREON 2 mg given subcutaneously once every 7 days (weekly) or insulin glargine once daily in addition to their existing oral antidiabetic therapy. Insulin glargine was dosed to a target fasting glucose concentration of 72 to 100 mg/dL.
The mean dose of insulin glargine was 10 units/day at baseline and 31 units/day at endpoint. At Week 26, 21% of insulin glargine treated patients were at fasting glucose goal.
A total of 456 patients were studied: 379 (83.1%) were White, 47 (10.3%) were Hispanic or Latino 25 (5.5%) were East Asian, 3 (0.7%) were Black or African American, and 2 (0.4%) were of West Asian ethnicity. Background therapy was either metformin (70%) or metformin plus sulfonylurea (30%). The mean baseline HbA1c was 8.3%.
The primary endpoint was change in HbA1c from baseline to Week 26 (or the last value at time of early discontinuation).
Efficacy Results
Treatment with BYDUREON once weekly resulted in a mean reduction in HbA1c from baseline at 26 weeks of -1.5%. The mean reduction in HbA1c seen in insulin glargine arm at 26 weeks was -1.3%. The difference in observed effect size between BYDUREON and glargine in this trial excluded the preÂspecified non-inferiority margin of +0.3%.
The proportion of patients with a Week 26 value achieving HbA1c of less than 7% at Week 26 were 57% and 48% for BYDUREON and insulin glargine, respectively. Patients who did achieve an HbA1c goal <7% and discontinued before Week 26 were not included as responders. The mean changes from baseline to Week 26 for fasting serum glucose in this study were -38 mg/dL and -50 mg/dL, and for body weight were -2.6 kg and +1.4 kg for BYDUREON and insulin glargine, respectively.
BYDUREON Versus BYETTA, Both As Monotherapy Or As Add-On To Metformin, A Sulfonylurea, A Thiazolidinedione, Or Combination Of Oral Agents
A 24-week, randomized, open-label trial was conducted to compare the safety and efficacy of BYDUREON to BYETTA in patients with type 2 diabetes and inadequate glycemic control with diet and exercise alone or with oral antidiabetic therapy, including metformin, a sulfonylurea, a thiazolidinedione, or combination of two of those therapies (Trial 4 -NCT00877890). Patients were randomly assigned to receive BYDUREON 2 mg subcutaneously once every 7 days (weekly) or BYETTA (10 mcg subcutaneously twice daily), in addition to existing oral antidiabetic agents. Patients assigned to BYETTA initiated treatment with 5 mcg twice daily then increased the dose to 10 mcg twice daily after 4 weeks.
A total of 252 patients were studied: 149 (59%) were White, 78 (31%) were Hispanic or Latino, 15 (6%) were Black or African American, and 10 (4%) were of Asian ethnicity. Patients were treated with diet and exercise alone (19%), a single oral antidiabetic agent (47%), or combination therapy of oral antidiabetic agents (35%). The mean baseline HbA1c was 8.4%.
The primary endpoint was change in HbA1c from baseline to Week 24 (or the last value at time of early discontinuation).
Efficacy Results
Treatment with BYDUREON 2 mg QW resulted in a statistically significantly greater mean HbA1c reduction compared to BYETTA 10 mcg twice daily. Change in body weight was a secondary endpoint. Twenty-four-week study results are summarized in Table 7.
Reductions from mean baseline (97/94 kg) in body weight were observed in both BYDUREON (-2.3 kg) and BYETTA (-1.4 kg) treatment groups.
Table 7: Results of 24-Week Trial of BYDUREON versus BYETTA, Both as Monotherapy or as Add-On to Metformin, a Sulfonylurea, a Thiazolidinedione, or Combination of Oral Agents in Patients with Type 2 Diabetes Mellitus (Trial 4)
|
BYDUREON 2 mg QW |
BYETTA 10 mcg twice daily* |
| Intent-to-Treat Population (N) |
129 |
123 |
| HbA1c (%) |
| Mean Baseline |
8.5 |
8.4 |
| Mean Change at Week 24† |
-1.6 |
-0.9 |
| Difference from BYETTA† [95% CI] |
−0.7
[−0.9, −0.4]‡ |
|
| Percentage Achieving HbA1c <7% at Week 24 (%) |
58‡ |
30 |
| Fasting Plasma Glucose (mg/dL) |
| Mean Baseline |
173 |
168 |
| Mean Change at Week 24 |
-25 |
-5 |
| Difference from BYETTA† [95% CI] |
−20
[−31, −10]‡ |
|
N = number of patients in each treatment group; mean change is least squares mean change; QW = once weekly.
* BYETTA 5 mcg twice daily before the morning and evening meals for 4 weeks followed by 10 mcg twice daily for 20 weeks.
† Least squares (LS) means are adjusted for baseline HbA1c strata, background antihyperglycemic therapy, and baseline value of the dependent variable (if applicable).
‡ p<0.001, treatment vs comparator. |
BYDUREON Versus Liraglutide, Both As Add-On To Metformin, A Sulfonylurea, Metformin + Sulfonylurea, Or Metformin + Pioglitazone Therapy
A 26-week open-label comparator-controlled trial was conducted to compare the safety and efficacy of BYDUREON to liraglutide in patients with type 2 diabetes whose glycemic control was inadequate with metformin, a sulfonylurea, metformin plus sulfonylurea, or metformin plus pioglitazone therapy (Trial 5 -NCT01029886). Patients were randomly assigned to receive BYDUREON 2 mg given subcutaneously once every 7 days (weekly) or liraglutide uptitrated from 0.6 mg/day to 1.2 mg/day, then 1.8 mg/day in addition to their existing oral antidiabetic therapy. Each titration was to be completed after at least one week, but could be delayed if the patient had severe nausea or vomiting as established by the investigator. Patients not tolerating the 1.8 mg/day dose of liraglutide by Week 4 were discontinued from the study.
A total of 911 patients were studied: 753 (82.7%) were White, 111 (12.2%) were Asian, 32 (3.5%) were American Indian or Alaska Native, 8 (0.9%) were of Black or African American ethnicity, 6 (0.7%) were multiple races, and 1 (0.1%) was Pacific Islander. Background therapy was either a single oral antidiabetic agent (35%) or a combination of oral antidiabetic agents (65%). The mean baseline HbA1c was 8.4%.
The primary endpoint was change in HbA1c from baseline to Week 26 (or the last value at time of early discontinuation).
Efficacy Results
Treatment with BYDUREON once weekly resulted in a mean reduction in HbA1c from baseline at 26 weeks of -1.3%. The mean reduction in HbA1c seen in the liraglutide arm at 26 weeks was -1.5%. The HbA1c reduction with BYDUREON did not meet predefined non-inferiority criteria compared to liraglutide 1.8 mg/day. The non-inferiority margin was set at +0.25% in this study. Results for the primary endpoint at 26 weeks are summarized in Table 8.
The proportion of patients with a Week 26 value achieving HbA1c of less than 7% at Week 26 were 48% and 56% for BYDUREON and liraglutide, respectively. Patients who did achieve an HbA1c goal <7% and discontinued before Week 26 were not included as responders. The mean changes from baseline to Week 26 for fasting serum glucose were -32 mg/dL and -38 mg/dL, and for body weight were -2.7 kg and -3.6 kg for BYDUREON and liraglutide, respectively.
Table 8: Results of 26-Week Trial of BYDUREON versus Liraglutide, Both as Add-On to Metformin, a Sulfonylurea, Metformin + Sulfonylurea, or Metformin + Pioglitazone Therapy in Patients with Type 2 Diabetes Mellitus (Trial 5)
|
BYDUREON 2 mg QW |
Liraglutide 1.8 mg/day |
| Intent-to-Treat Population (N) |
461 |
450 |
| HbA1c (%) |
| Mean Baseline |
8.5 |
8.4 |
| Mean Change at Week 26* |
-1.3 |
-1.5 |
| Difference from liraglutide* [95% CI] |
0.2
[0.08, 0.331 |
|
N = number of patients in each treatment group; mean change is least squares mean change; QW = once weekly. HbA1c change data at 26 weeks were available from 85% and 86% of the randomized subjects in the BYDUREON and liraglutide groups, respectively.
* Least squares means were obtained using a mixed model repeated measure analysis with treatment, country, OAD stratum, baseline HbA1c stratum, visit, baseline HbA1c, and treatment by visit interaction as fixed effects, and subject as a random effect. |
BYDUREON In Combination With Dapagliflozin Versus BYDUREON Alone And Dapagliflozin Alone, All As Add-On To Metformin
A 28-week double-blind comparator-controlled trial was conducted to compare the efficacy of BYDUREON and dapagliflozin (an SGLT2 inhibitor) to BYDUREON alone and dapagliflozin alone in patients with type 2 diabetes with inadequate glycemic control with metformin therapy (Trial 6 -NCT02229396). All patients entered a 1-week placebo lead–in period. Patients with HbA1c ≥8.0% and ≤12% and on metformin at a dose of at least 1,500 mg per day were randomly assigned to receive either BYDUREON 2 mg given subcutaneously once every 7 days (weekly) plus dapagliflozin 10 mg once daily, BYDUREON 2 mg given subcutaneously once weekly, or dapagliflozin 10 mg once daily.
A total of 694 patients were studied; 580 (83.6%) were White, 96 (13.8%) were Black or African American, 5 (0.7%) were of Asian ethnicity, 2 (0.3%) were American Indian or Alaska Native and 11 (1.6%) were classified otherwise. The mean baseline HbA1c was 9.3%.
The primary endpoint was change in HbA1c from baseline to Week 28.
Efficacy Results
At Week 28, BYDUREON in combination with dapagliflozin provided statistically significantly greater reductions in HbA1c (-1.77%) compared to BYDUREON alone (-1.42%, p=0.012) and dapagliflozin alone (-1.32%, p=0.001). BYDUREON in combination with dapagliflozin provided statistically significantly greater reductions in FPG (-57.35 mg/dL) compared to BYDUREON alone (-40.53, p <0.001) and dapagliflozin alone (-44.72 mg/dL, p=0.006).
BYDUREON Versus Placebo, Both As Add-On To Basal Insulin Or Basal Insulin + Metformin Therapy
A 28-week, double-blind, placebo-controlled trial was conducted to compare the safety and efficacy of BYDUREON to placebo when added to basal insulin glargine, with or without metformin, in patients with type 2 diabetes with inadequate glycemic control (Trial 7 -NCT02229383). Patients on sulfonylurea therapy discontinued sulfonylurea. Patients on metformin continued on the same dose of metformin. All patients initially entered an 8-week insulin dose-titration phase. Insulin glargine was to be titrated every 3 days with an aim of achieving a target fasting plasma glucose concentration of 72 to 99 mg/dL. Following the titration period, patients with HbA1c ≥7.0% and ≤10.5% were then randomly assigned to receive either BYDUREON 2 mg given subcutaneously once every 7 days (weekly) or placebo once every 7 days (weekly).
A total of 460 patients were studied: 400 (87.0%) were White, 47 (10.2%) were Black or African American, 6 (1.3%) were of Asian ethnicity, 1 (0.2%) was American Indian or Alaska Native, 1 (0.2%) was Pacific Islander and 5 (1.1%) were classified otherwise.
The primary endpoint was the change in HbA1c from baseline to Week 28.
Efficacy Results
Compared to placebo, treatment with BYDUREON resulted in a statistically significant reduction in mean HbA1c from baseline to Week 28 (Table 9).
The mean change in fasting plasma glucose from baseline to Week 28 was -12.50 mg/dL for BYDUREON and -2.26 mg/dL for placebo. The mean change from baseline to Week 28 in body weight was -0.92 kg for BYDUREON and +0.38 kg for placebo.
Table 9: Results of 28-Week Trial of BYDUREON versus Placebo, Both as Add-On to Insulin Glargine or Insulin Glargine + Metformin (Trial 7)
|
BYDUREON 2 mg QW |
Placebo QW |
| Intent-to-Treat Population (N) |
231 |
229 |
| Mean HbA1c (%) |
| Mean Baseline |
8.53 |
8.53 |
| Mean Change at Week 28* |
-0.88 (0.070) |
-0.24 (0.069) |
| Difference from Placebo [95% CI] |
-0.641†
[-0.83, -0.45] |
|
| Percentage Achieving HbA1c <7.0% at Week 28 (%)‡ |
32.5† |
7.0 |
N = number of patients in each treatment group, CI=confidence interval, QW=once weekly. Note: mean change is least squares mean change.
*Adjusted LS means and treatment group difference(s) in the change from baseline values at Week 28 using a multiple imputation method that models a “wash-out” for patients having missing data who discontinued treatment. ANCOVA was used with treatment, region, baseline HbA1c stratum (<9.0% or ≥9.0%), and baseline SU-use stratum (yes vs. no) as fixed factors, and baseline value as a covariate.
† p-value <0.001 (adjusted for multiplicity).
‡ Categories are derived from continuous measurements. All patients with missing endpoint data are imputed as non-responders. Treatment comparison is based on Cochran-Mantel-Haenszel (CMH) test stratified by baseline HbA1c (<9.0% or ≥9.0%), and baseline SU-use stratum (yes vs. no). P-values are from the general association statistics.
Analyses include measurements post rescue therapy and post premature discontinuation of study medication. |
EXSCEL Cardiovascular Outcomes Trial In Adult Patients With Type 2 Diabetes Mellitus
EXSCEL was a multinational, placebo-controlled, double-blind, randomized, parallel group pragmatic study that evaluated cardiovascular (CV) outcomes during treatment with BYDUREON in adult patients with type 2 diabetes and any level of CV risk when added to the current usual care (NCT01144338). A total of 14,752 adult patients were randomized 1:1 to either BYDUREON 2 mg given subcutaneously once weekly or placebo and followed as in routine clinical practice for a median of 38.7 months with a median treatment duration of 27.8 months.
Ninety six percent of the patients in both treatment groups completed the study in accordance with the protocol, and the vital status was known at the end of the study for 98.9% and 98.8% of the patients in the BYDUREON and placebo group, respectively. The mean age at study entry was 62 years (21 to 92 years with 8.5% of the patients ≥75 years). Approximately 62.0% of the patients were male, 75.8% were White, 9.8% were Asian, 6.0% were Black or African American, and 20.5% were of Hispanic or Latino ethnicity. The mean BMI was 32.7 kg/m² and the mean duration of diabetes was 13.1 years. Approximately 49.3% had mild renal impairment (estimated glomerular filtration rate [eGFR] ≥60 to ≤89 mL/min/1.73 m²) and 21.6% had moderate renal impairment (eGFR ≥30 to ≤59 mL/min/1.73 m²).
The mean HbA1c was 8.1%. At baseline, 1.5% of patients were not treated with either oral antidiabetic medications or insulin, 42.3% were treated with one oral antidiabetic medication and 42.4% were treated with two or more oral antidiabetic medications. Usage of oral antidiabetic medications included metformin (76.6%), sulfonylurea (36.6%), dipeptidyl peptidase-4 (DPP-4) inhibitors (14.9%), thiazolidinediones (3.9%), and SGLT2 inhibitors (0.9%). Overall insulin usage was 46.3% (13.8% with insulin alone and 32.6% with insulin and one or more oral antidiabetic medications).
Overall, at baseline, 26.9% of patients did not have established cardiovascular (CV) disease, while 73.1% had established CV disease. The concomitant use of CV medications (e.g., ACE inhibitors, angiotensin receptor blockers, diuretics, beta blockers, calcium channel blockers, antithrombotic and anticoagulants, and lipid-lowering agents) was similar in the BYDUREON and placebo groups. At baseline, the mean systolic blood pressure was 135.5 mmHg, the mean diastolic blood pressure was 78.1 mmHg, the mean LDL was 95.0 mg/dL, and the mean HDL was 44.0 mg/dL.
The primary endpoint in EXSCEL was the time to first confirmed Major Adverse Cardiac Event (MACE) from randomization. MACE was defined as occurrence of either a cardiovascular (CV)-related death, or a nonfatal myocardial infarction (MI) or a nonfatal stroke. All-cause mortality, CV-related death, and fatal or nonfatal MI or stroke, hospitalization for acute coronary syndrome, and hospitalization for heart failure were also assessed as secondary endpoints.
A Cox proportional hazards model was used to test for non-inferiority against the pre-specified risk margin of 1.3 for the hazard ratio of MACE and superiority on MACE if non-inferiority was demonstrated. Type-1 error was controlled across multiple tests using a hierarchical testing strategy.
MACE Results
BYDUREON did not increase the risk of MACE in adult patients with type 2 diabetes mellitus (HR: 0.91; 95% CI: 0.832, 1.004; P<0.001 for non-inferiority; P=0.06 for superiority). See results in Table 10 and Figure 2. The incidence of MACE in patients with and without established CV disease was 13.4% in the BYDUREON group versus 14.6% in the placebo group and 6.0% (BYDUREON) versus 5.9% (placebo), respectively. Five hundred and seven (507) patients (6.9%) died in the BYDUREON group versus 584 (7.9%) in the placebo group.
Table 10: Analysis of Primary Composite Endpoint MACE and Its Components in Adult Patients with Type 2 Diabetes (EXSCEL)
|
BYDUREON
N=7356 |
Placebo
N=7396 |
HR* (95% CI) |
| MACE Composite of CV death, nonfatal MI or nonfatal stroke (time to first confirmed event) |
839 (11.4%) |
905 (12.2%) |
0.91 (0.832, 1.004) |
| Cardiovascular Death |
340 (4.6%) |
383 (5.2%) |
0.88 (0.76, 1.02) |
| Nonfatal Myocardial Infarction |
466 (6.3%) |
480 (6.5%) |
0.96 (0.85, 1.09) |
| Nonfatal Stroke |
169 (2.3%) |
193 (2.6%) |
0.86 (0.70, 1.06) |
N=number of patients in each treatment group, HR=hazard ratio, CI=confidence interval, CV=cardiovascular, MI=myocardial infarction.
* HR (active/placebo) and CI are based on Cox proportional hazards regression model, stratified by established CV disease, with treatment group only as explanatory variable. |
Figure 2: Time to First Adjudicated MACE in Adult Patients with Type 2 Diabetes (EXSCEL)
HR=hazard ratio, CI=confidence interval.
Glycemic Control Trial In Pediatric Patients 10 Years Of Age And Older With Type 2 Diabetes Mellitus
The efficacy and safety of BYDUREON 2 mg given subcutaneously once weekly or placebo was evaluated in a 24-week randomized, double-blind, placebo-controlled, parallel-group study (Trial 8 -NCT01554618) in 82 patients aged 10 to 17 years with type 2 diabetes treated with diet and exercise alone or in combination with a stable dose of oral antidiabetic agents and/or insulin. This study included a 28-week open-label long-term extension in which patients in both treatment groups received BYDUREON 2 mg given subcutaneously once weekly after the 24-week controlled period.
In this trial, 88% of patients completed the assessment period. The mean age at study entry was 15.1 years (13% were 11 to 12 years old, 59% were 13 to 16 years old and 28% were older than 16 years). Approximately 42% of the patients were male, 43% were White, 4% were Asian, 31% were Black or African American, 6% were American Indian or Alaska Native, and 44% were of Hispanic or Latino ethnicity. . The mean body weight was 100.6 kg (67% were in ≥97 weight percentile group, 26% in ≥85 to <97 and 6%in ≥3 to <85), mean BMI was 36.4 kg/m² and the mean duration of diabetes was 2.3 years.
At baseline, mean HbA1c was 8.17%, 12.2% of patients were not treated with either oral antidiabetic medications or insulin, 40.2% were treated with one oral antidiabetic medication and 1.2% were treated with two oral antidiabetic medications. 79.3% of patients were receiving metformin and 1.2% were receiving sulfonylurea. Overall insulin usage was 46.3% (8.5% with insulin alone and 37.8% with insulin and one other oral antidiabetic medication).
The primary endpoint of the study was the change in HbA1c from baseline to Week 24.
Efficacy Results
BYDUREON was superior to placebo in reducing HbA1c (Table 11).
The mean changes from baseline to Week 24 for body weight were -0.17 kg with (SE 0.7) and +0.88 kg (SE 1.0) for BYDUREON and placebo, respectively.
Table 11: Results of 24-Week Trial of BYDUREON versus Placebo, Both alone or in Combination with Oral Antidiabetic Agents and/or Insulin in Pediatric Patients 10 Years of Age and Older with Type 2 Diabetes Mellitus (Trial 8)
|
BYDUREON 2 mg QW |
Placebo QW |
| Intent-to-Treat Population (N) |
58 |
24 |
| HbA1c (%) |
| Mean Baseline |
8.13 |
8.28 |
| Mean Change at Week 24 (SE)* |
-0.25 (0.21) |
0.45 (0.29) |
| Difference from Placebo (95% CI) |
-0.71† (-1.42, 0) |
|
| HbA1c<7% |
|
| Percentage achieved goal at Week 24 |
31.0 |
8.3 |
| Fasting Plasma Glucose (mg/dL) |
| Mean Baseline |
165.2 |
170.5 |
| Mean Change at Week 24 (SE)* |
-1.3 (8.1) |
16.2 (11.9) |
* Adjusted LS means and treatment group difference(s) in the change from baseline values at Week 24 using a multiple imputation method that models a “wash-out” for patients having missing data who discontinued treatment. ANCOVA was used with treatment, region as fixed factors, and baseline HbA1c value as a covariate. SE – standard error.
† p<0.05
‡ Adjusted LS means in the change from baseline values at Week 24 using a multiple imputation method that models a “wash-out” for patients having missing data who discontinued treatment. ANCOVA was used with treatment, region, as fixed factors, and baseline FPG value as a covariate. |