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Background: Exenatide therapy is effective in combination with metformin or sulfonylureas for treating type 2 diabetes. Thiazolidinediones (TZDs) also are commonly used, but the efficacy of exenatide with a TZD has not been reported.Objective: To compare the effects of exenatide versus placebo on glycemic control.Design: Placebo run-in, randomized, double-blind, placebo-controlled trial conducted from May 2004 to August 2005.Setting: 49 sites in Canada, Spain, and the United States.Patients: 233 (exenatide group, n = 121; placebo group, n = 112) patients with type 2 diabetes that was suboptimally controlled with TZD treatment (with or without metformin). Mean (+/-SE) baseline glycated hemoglobin A1c level was 7.9% +/- 0.1%.Interventions: Subcutaneous abdominal injections of 10 microg of exenatide or placebo twice daily, added to a TZD (with or without metformin) for 16 weeks.Measurements: The primary outcome was change from baseline in hemoglobin A1c level. Other outcomes were fasting serum glucose level, body weight, self-monitored blood glucose level, and any adverse events.Results: Exenatide treatment reduced hemoglobin A(1c) level (mean difference, -0.98% [95% CI, -1.21% to -0.74%]), serum fasting glucose level (mean difference, -1.69 mmol/L [-30.5 mg/dL] [CI, -2.22 to -1.17 mmol/L {-40.0 to -21.1 mg/dL}]), and body weight (mean difference, -1.51 kg [CI, -2.15 to -0.88 kg]). Sixteen percent of patients in the exenatide group and 2% of patients in the placebo group discontinued treatment because of adverse events. In the exenatide group, 40% (n = 48) of patients experienced nausea (mostly mild [n = 21] or moderate [n = 19]), 13% experienced vomiting, and 11% experienced hypoglycemia. In the placebo group, 15% of patients experienced nausea, 1% experienced vomiting, and 7% experienced hypoglycemia.Limitations: Combinations with TZDs and sulfonylureas were not tested. Trial duration was relatively short. Only 71% and 86% of patients in the exenatide and placebo groups, respectively, completed the study.Conclusions: Exenatide therapy improved glycemic control, reduced body weight, and caused gastrointestinal symptoms more than placebo in patients with type 2 diabetes that was suboptimally controlled with TZD therapy. ClinicalTrials.gov registration number: NCT00099320. For more information on exenatide click here. [ABSTRACT FROM AUTHOR]

Introduction: Efpeglenatide is a long-acting glucagon-like peptide-1 receptor agonist being developed to improve glycemic control in type 2 diabetes (T2D). In the BALANCE 205 study (NCT02075281), efpeglenatide significantly reduced body weight versus placebo in patients with obesity, or overweight with comorbidities, and without T2D. These subanalyses explore the efficacy and safety of efpeglenatide in subgroups of patients with pre-diabetes and stratified by body mass index (BMI) or age from the BALANCE study., Research Design and Methods: The 20-week BALANCE study randomized patients with BMI ≥30 kg/m 2 or ≥27 kg/m 2 with comorbidities, and without diabetes, to efpeglenatide 4 mg or 6 mg once weekly, 6 mg or 8 mg once every 2 weeks, or placebo. For these subanalyses, patients were stratified by pre-diabetes status (glycated hemoglobin (HbA 1c ) 5.7%-6.4% (39-46 mmol/mol) or fasting plasma glucose (FPG) 100-125 mg/dL) and by BMI or age < or ≥ median values (34.9 kg/m 2 and 44 years, respectively) at baseline., Results: In patients with pre-diabetes at baseline, all efpeglenatide doses led to greater proportions of patients reverting to normoglycemia (40.6%-64.3%) versus placebo (10.0%), and greater reductions in HbA 1c (0.30%-0.38%), FPG (7.7-14.1 mg/dL), and weight (5.6-7.3 kg) versus placebo (nominal p<0.05 for all). In patients with BMI or age < or ≥ median, greater reductions in weight were observed with all efpeglenatide doses versus placebo (nominal p<0.01 for all). The most common adverse events in patients receiving efpeglenatide across patient subgroups were gastrointestinal adverse events., Conclusions: These results are consistent with the overall BALANCE population and suggest beneficial effects of efpeglenatide on glycemic control and body weight regardless of pre-diabetes status, age, or BMI at baseline. The effects of efpeglenatide on glycemic control in patients with pre-diabetes suggest it might help reduce the likelihood of at-risk patients developing diabetes., Competing Interests: Competing interests: REP has served as a consultant for AstraZeneca, Glytec, Janssen Pharmaceuticals, Merck, MundiPharma, Novo Nordisk, Pfizer, Sanofi, Sanofi US Services, Scohia Pharma, and Sun Pharmaceutical Industries; has received grants and research support from Hanmi Pharmaceutical, Janssen Pharmaceuticals, Metavention, Novo Nordisk, Poxel SA, and Sanofi; and has received honoraria from Novo Nordisk; honoraria and fees for these activities were directed to a non-profit organization with the exception of those from Sanofi US Services, which were personal fees. SB is an employee of Hanmi Pharmaceutical. MET is a consultant of ProSciento; has received consulting fees from Atrogi, CeQur SA, Hanmi Pharmaceutical, Kinexum, Novo Nordisk, and Servier; and is on the Data Monitoring Board for Profil. MH is an employee and shareholder of ProSciento and has received grants from Hanmi Pharmaceutical. OH is an employee of Hanmi Pharmaceutical. JS is an employee and shareholder of Sanofi. AS was an employee of Sanofi during the development of this publication. CHS was an employee and shareholder of Sanofi during the development of this publication. SJ has received personal fees from AstraZeneca, Boehringer Ingelheim, Lilly, MSD, Novo Nordisk, and Sanofi. K-HY has nothing to declare., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: To evaluate the effects of efpeglenatide, a long-acting glucagon-like peptide-1 receptor agonist (GLP-1 RA), on gastric emptying, glucose metabolism, and islet beta-cell function versus liraglutide and placebo in people with type 2 diabetes., Research Design and Methods: This phase Ib study (ClinicalTrials.gov identifier: NCT02059564) randomized participants (n=47) to three cohorts. Within the first two cohorts, participants were randomized to placebo, efpeglenatide 6 mg weekly (QW; first cohort), or efpeglenatide 16 mg monthly (QM; second cohort). The third cohort received liraglutide 1.8 mg daily (QD). Gastric emptying was assessed through the pharmacokinetic (PK) profile of acetaminophen at baseline and steady state. Glucose metabolism and beta-cell function were assessed based on mixed-meal tolerance testing and a graded glucose infusion procedure., Results: Treatment duration was approximately 3 months for efpeglenatide 16 mg QM and 1 month for efpeglenatide 6 mg QW and liraglutide. At peak drug concentrations, efpeglenatide 6 mg QW was non-inferior to liraglutide 1.8 mg QD in delaying gastric emptying, as assessed by acetaminophen PK (lower bound of 90% CI for the efpeglenatide:liraglutide ratio >0.8 for area under the curve (AUC) 0-120 , AUC 0-180 , AUC 0-360 and maximum concentration (C max )). Efpeglenatide 16 mg QM did not decrease the rate of gastric emptying to as great an extent as liraglutide (ie, non-inferiority was not shown). Compared with liraglutide, both efpeglenatide dosing regimens demonstrated comparable or more favorable glucometabolic effects and improved beta-cell function. All gastrointestinal adverse events reported with efpeglenatide were mild or moderate in severity and transient over treatment and follow-up., Conclusions: The glucometabolic effects of efpeglenatide 6 mg QW and 16 mg QM were comparable to liraglutide. Additional studies are necessary to further examine these benefits of efpeglenatide., Trial Registration Number: NCT02059564., Competing Interests: Competing interests: MH is an employee and shareholder of ProSciento. JK was an employee of Hanmi Pharmaceutical at the time the study was conducted. OH is an employee of Hanmi Pharmaceutical. MET is a consultant of ProSciento; has received consulting fees from Atrogi, CeQur SA, Hanmi Pharmaceutical, Kinexum, Novo Nordisk, and Servier; and is on the Data Monitoring Board for Profil. CHS was an employee and shareholder of Sanofi during the development of this publication. JS is an employee and shareholder of Sanofi. IO was an employee of Sanofi during the development of this publication and is a shareholder of Lexicon Pharmaceuticals. LM is a consultant to ProSciento and to TVM Capital Life Science., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Aim: To assess the efficacy, safety and pharmacokinetic/pharmacodynamic properties of efpeglenatide, a long-acting glucagon-like peptide-1 receptor agonist, in patients with type 2 diabetes (T2D)., Research Design and Methods: Two randomized, double-blind, placebo-controlled phase 2 trials were conducted. The single-dose study (n = 48) was a first-in-patient, sequential dose-escalation study. Patients received a single subcutaneous injection of efpeglenatide (2-100 μg/kg) or placebo. The repeated-dose study (n = 71) was a multiple-ascending-dose trial. Patients received weekly (1, 2 or 4 mg once weekly; 8-week period) or monthly (8, 12 or 16 mg once monthly; 9-week period) subcutaneous injections of efpeglenatide or placebo (without titration)., Results: Both studies demonstrated dose-proportional increases in efpeglenatide serum concentrations. The median time to attain maximum serum concentration (t max ) for efpeglenatide ranged from 72 to 144 hours in the single-dose study and from 48 to 120 hours in the repeated-dose study (following final dose). Geometric mean t 1/2 ranged from 135 to 180 hours across studies. Peak-to-trough ratios in the repeated-dose study ranged from 1.3 to 1.4 with once-weekly dosing and from 5.9 to 12.9 with once-monthly dosing. Following a single dose of efpeglenatide 14-100 μg/kg, fasting plasma glucose and postprandial plasma glucose levels were decreased at week 1 and remained below baseline levels for ≥3 weeks post-dosing. Repeated doses of efpeglenatide led to significant reductions in glycated haemoglobin vs placebo. In both studies, efpeglenatide was generally well tolerated. Gastrointestinal disorders were the most frequently reported treatment-emergent adverse events in efpeglenatide-treated patients., Conclusions: The delayed t max, long half-life, and low peak-to-trough ratios observed demonstrate potential for improved efficacy and dosing flexibility, with good tolerability of efpeglenatide in patients with T2D., (© 2020 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)

Aims: To determine the optimal dose(s) of once-monthly administration of efpeglenatide, a long-acting glucagon-like peptide-1 receptor agonist (GLP-1RA), in patients with type 2 diabetes (T2D) inadequately controlled on metformin., Materials and Methods: In this phase 2, randomized, placebo-controlled, double-blind trial (NCT02081118), patients were randomized 1:1:1:1 to subcutaneous efpeglenatide (8, 12 or 16 mg once monthly; n = 158) or placebo (n = 51). The 16-week treatment period included a 4-week titration phase with once-weekly efpeglenatide 4 mg, followed by one dose of efpeglenatide 8 mg once monthly and two doses of the assigned once-monthly dose. The primary endpoint was change in glycated haemoglobin (HbA1c) from baseline to week 17., Results: All efpeglenatide doses significantly reduced HbA1c versus placebo (P < 0.0001 for all). Overall, the least squares mean difference in HbA1c reductions between efpeglenatide and placebo was -7.7 mmol/mol (-0.71%; baseline to week 17). At week 17, a significantly greater proportion of efpeglenatide patients had an HbA1c level <53 mmol/mol (<7%) versus placebo (48.7% vs. 30.6%; P = 0.0320). Significant body weight loss occurred across all efpeglenatide doses (placebo-corrected reduction -2.0 kg [efpeglenatide overall]; P = 0.0003). The safety profile was consistent with GLP-1RAs, with gastrointestinal (GI) disorders being the most common treatment-emergent adverse events. Fluctuations in effects on glucose levels and rates of GI events occurred between peak and trough efpeglenatide concentrations., Conclusions: Efpeglenatide once monthly (following once-weekly titration) has significant benefits with regard to HbA1c and weight reduction versus placebo in patients with T2D. Further studies are needed to evaluate the long-term efficacy and safety of efpeglenatide once monthly., (© 2020 John Wiley & Sons Ltd.)

Aim: To evaluate the safety of efpeglenatide, a long-acting glucagon-like peptide-1 receptor agonist (GLP-1RA), and its effects on body weight management in adults without diabetes., Materials and Methods: In this phase II, randomized, placebo-controlled, double-blind trial, participants with a body mass index (BMI) ≥30 kg/m 2 or ≥27 kg/m 2 with comorbidity were randomized 1:1:1:1:1 to efpeglenatide (4 mg once weekly, 6 mg once weekly, 6 mg once every 2 wk, or 8 mg once every 2 wk; n = 237) or placebo (n = 60) in combination with a hypocaloric diet. The primary endpoint was body weight change from baseline after 20 wk of treatment, assessed using a mixed-effect model with repeated measures with an unstructured covariance matrix over all post-screening visits; treatment comparisons were based on least squares mean estimates., Results: Over 20 wk, all doses of efpeglenatide significantly reduced body weight from baseline versus placebo (P < 0.0001), with placebo-adjusted reductions ranging between -6.3 kg (6 mg once every 2 wk) and -7.2 kg (6 mg once weekly). Greater proportions of efpeglenatide-treated participants had body weight loss of ≥5% or ≥10% versus placebo (P < 0.01, all comparisons). Efpeglenatide led to significant improvements in glycaemic variables (fasting plasma glucose and glycated haemoglobin) and lipid profiles (cholesterol, triglycerides) versus placebo. Rates of study discontinuations as a result of adverse events ranged from 5% to 19% with efpeglenatide. Gastrointestinal effects were the most common treatment-emergent adverse events., Conclusions: Efpeglenatide once weekly and once every 2 wk led to significant body weight reduction and improved glycaemic and lipid variables versus placebo. It was also well tolerated for weight management in adults without diabetes., (© 2019 John Wiley & Sons Ltd.)

Objective: To explore the efficacy, safety, and tolerability of once-weekly efpeglenatide, a long-acting glucagon-like peptide 1 receptor agonist (GLP-1 RA), in early type 2 diabetes (T2D) (drug naive or on metformin monotherapy)., Research Design and Methods: EXCEED 203 was a 12-week, randomized, placebo-controlled, double-blind, parallel-group, dose-ranging study of efpeglenatide once weekly referenced to open-label liraglutide 1.8 mg (exploratory analysis). Participants, ∼90% on metformin monotherapy, were randomized to one of five efpeglenatide doses (0.3, 1, 2, 3, or 4 mg q.w.; n = 181), placebo ( n = 37), or liraglutide (≤1.8 mg daily; n = 36). The primary efficacy end point was change in HbA 1c from baseline to week 13., Results: From a baseline HbA 1c of 7.7-8.0% (61.0-63.9 mmol/mol), all efpeglenatide doses ≥1 mg significantly reduced HbA 1c versus placebo (placebo-adjusted least squares [LS] mean changes 0.6-1.2%, P < 0.05 for all) to a final HbA 1c of 6.3-6.8% (45.4-50.6 mmol/mol); masked efpeglenatide 4 mg was noninferior to open-label liraglutide. Greater proportions treated with efpeglenatide ≥1 mg than placebo achieved HbA 1c <7% (61-72% vs. 24%, P < 0.05 for all), and greater reductions in body weight were observed with efpeglenatide 3 and 4 mg versus placebo (placebo-adjusted LS mean differences -1.4 and -2.0 kg, respectively, P < 0.05 for both). Rates of nausea and vomiting were consistent with other GLP-1 RAs and rapidly subsided after the initial 2 weeks. No neutralizing antibodies were detected with efpeglenatide., Conclusions: Efpeglenatide once weekly led to significant reductions in HbA 1c and weight, with a safety profile consistent with the GLP-1 RA class in patients with early T2D mostly on metformin monotherapy., (© 2019 by the American Diabetes Association.)

This post-hoc analysis of the DURATION-3 study aimed to identify factors associated with sustained glycaemic response with exenatide once weekly (QW) or insulin glargine (IG) among patients with type 2 diabetes. Response was defined as achieving treatment target of HbA1c <7.0% (<53 mmol/mol) at Week 26; sustained responders maintained the treatment target for ≥80% of remaining visits, including one during the final 6 months. Of 467 patients, 287 (61.5%) completed 156 weeks of treatment. At Week 26, 175 patients (61.0%) (exenatide QW, n = 95; IG, n = 80) achieved an HbA1c response. At Week 156, 84 of 175 responders (48.0%) had sustained response, with more sustained responders with exenatide QW (22.7% vs 13.9% with IG; P < 0.03). Logistic regression identified three predictors of sustained response: (a) exenatide QW vs IG treatment (odds ratio, 2.584 [95% confidence interval, 1.288-5.187]; P = 0.0075), (b) lower HbA1c at Week 26 (0.139 [0.053-0.366]; P < 0.0001), and (c) lower fasting serum glucose at Week 26 (0.693 [0.541-0.888]; P = 0.0037). A regression model was used to estimate the likelihood of sustained response with either treatment. This analysis provides a helpful tool for predicting sustained response with exenatide QW or IG., (© 2018 John Wiley & Sons Ltd.)

As Type 2 diabetes progresses, treatment is intensified with additional therapies in an effort to manage hyperglycaemia effectively and therefore avoid complications. When greater efficacy is required, options for injectable treatments include glucagon-like peptide-1 receptor agonists and insulin, which may be added on to oral glucose-lowering treatments. Among individuals receiving long-acting basal insulin as their first injectable treatment, ~40-60% are unable to achieve or maintain their target HbA 1c goals. For these people, treatment intensification options are relatively limited and include the addition of short-acting prandial insulin or a glucagon-like peptide-1 receptor agonist. Glucagon-like peptide-1 receptor agonists vary in their effects, with short- and long-acting agents having a greater impact on postprandial and fasting hyperglycaemia, respectively. Studies comparing treatment intensification options have found both glucagon-like peptide-1 receptor agonists and prandial insulin to be effective in reducing HbA 1c concentrations; however, recipients of glucagon-like peptide-1 receptor agonists lost weight and had a greater frequency of gastrointestinal adverse events, whereas those receiving prandial insulin gained weight and had a greater incidence of hypoglycaemia. In addition to the separate administration of a glucagon-like peptide-1 receptor agonist and basal insulin, fixed-ratio combinations of a glucagon-like peptide-1 receptor agonist and basal insulin offer a single administration for both treatments but have less flexibility in dose titration than treatment with their individual components. For individuals who require treatment intensification beyond basal insulin, use of these various options allows physicians to target the individual needs of their patients for the achievement of optimal long-term glycaemic control., (© 2018 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.)

Aims: To evaluate the 3-year efficacy and safety of exenatide once weekly (QW) for type 2 diabetes (T2D) in a large clinical population., Methods: This post hoc analysis of three DURATION studies examined pooled efficacy and adverse events with exenatide QW from the 2.5- to 3-year completer populations; insulin glargine (glargine) was a reference (DURATION-3). Patients randomized to exenatide QW during the controlled study periods continued controlled treatment (DURATION-3) or single-arm treatment (DURATION-1; DURATION-2) with exenatide QW for the study duration., Results: In the exenatide QW group (N=329), reductions from baseline in HbA1c, fasting glucose, and body weight were maintained from weeks 4 to 156 (HbA1c: -1.1±1.3%; fasting glucose: -1.7±2.7mmol/L; body weight: -2.4±5.6kg; P<0.05). Glycemic efficacy with exenatide QW and glargine was similar (HbA1c reduction: -0.8±1.0%; N=158); body weight increased with glargine (+2.0±4.9kg). Variable reductions in systolic blood pressure and low-density lipoprotein cholesterol occurred with exenatide QW. At week 156, 48.3% and 30.7% of exenatide QW recipients achieved HbA1c goals of <7.0% and ≤6.5%, respectively. No new safety or tolerability issues were identified., Conclusions: Exenatide QW improved glycemic outcomes and was well tolerated in patients with T2D for up to 156weeks., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Exenatide once weekly, a glucagon-like peptide-1 receptor agonist (GLP-1RA), is approved as an adjunct to diet and exercise for the treatment of adults with type 2 diabetes mellitus. Exenatide acts by binding to and activating glucagon-like peptide-1 receptors, thereby stimulating glucose-dependent insulin secretion, suppressing glucose-dependent glucagon secretion, slowing gastric emptying, and increasing feelings of satiety. Gradual increases in drug level ("autotitration") after the initiation of a fixed exenatide 2-mg weekly dose achieve minimal effective (~50 pg/mL) and steady-state (~300 pg/mL) concentrations by 2 weeks and 6 to 8 weeks, respectively. The purpose of this study was to examine pharmacodynamic outcomes with exenatide once weekly and to determine whether changes are secondary to weight loss and thus delayed by the sequential nature of responses., Methods: This post hoc analysis evaluated trials in the exenatide once-weekly development program. Outcomes included glycosylated hemoglobin (HbA1c), weight, fasting serum or plasma glucose (FG), lipids, and blood pressure (BP) at weeks 2, 4, and 24. Relationships between changes from baseline in these outcomes and changes in weight were examined. The effect of nausea and vomiting (adverse events characteristic of GLP-1RAs) on weight loss was also assessed., Findings: Pooled data were analyzed from 12 trials in which 2190 patients received exenatide once weekly. Patients had a mean HbA1c level of 8.4% and weight of 87 kg at baseline. Exenatide once weekly produced significant improvements in HbA1c, FG, weight, and systolic BP at weeks 2 and 4, with continuous improvements through week 24. There were no clinically meaningful correlations between weight loss and improvements in pharmacodynamic outcomes at weeks 2, 4, or 24. Patients had significant reductions in weight at weeks 2, 4, and 24 regardless of whether they experienced nausea and/or vomiting during the study, although patients with at least 1 nausea/vomiting event had greater weight loss at week 24 than those who did not., Implications: Improvements in pharmacodynamic end points occurred early in treatment with exenatide once weekly, before steady-state plasma concentrations. These early effects did not seem to be secondary to weight loss and are likely the direct effects of exenatide., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the 5-year efficacy and safety of once weekly exenatide., Patients and Methods: The Diabetes Therapy Utilization: Researching Changes in A1C, Weight and Other Factors Through Intervention with Exenatide Once Weekly (DURATION-1) randomized clinical trial consisted of a 30-week controlled phase (2 mg of exenatide once weekly vs 10 μg of exenatide twice daily) with an open-ended uncontrolled extension (once weekly exenatide only) in patients with type 2 diabetes mellitus on background glucose-lowering therapies (April 15, 2006, through February 21, 2012). At week 30, patients initially receiving 10 μg of exenatide twice daily switched to 2 mg of exenatide once weekly. Study end points included changes from baseline in hemoglobin A1c, fasting plasma glucose, weight, lipids, and blood pressure. Long-term safety data included adverse events, liver and renal function, and heart rate., Results: Of 258 extension-phase patients, 153 (59.3%) completed 5 years of treatment. Hemoglobin A1c levels were significantly and durably reduced from baseline (least-squares mean, -1.6%; 95% CI, -1.8% to -1.4%; vs -1.9% for exenatide once weekly at week 30), and 65 (43.9%) of 148 patients achieved hemoglobin A1c levels of less than 7.0%. Significant improvements in fasting plasma glucose level (-28.8 mg/dL; 95% CI, -36.2 to -21.5 mg/dL), weight (-3.0 kg; 95% CI, -4.6 to -1.3 kg), lipids, and diastolic blood pressure were observed, with minimal heart rate increase. Frequencies of nausea and injection-site reactions or nodules were decreased vs the initial 30-week controlled phase. Minor hypoglycemia occurred predominantly with sulfonylurea use, and no major hypoglycemia or new safety signals were observed., Conclusion: Long-term once weekly exenatide treatment was generally well tolerated with sustained glycemic improvement, weight reduction, and improved markers of cardiovascular risk in patients with type 2 diabetes., Trial Registration: clinicaltrials.gov Identifier: NCT00308139., (Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Background: When patients with type 2 diabetes start their first injectable therapy, clinicians can choose between glucagon-like peptide-1 (GLP-1) receptor agonists and basal insulins. In DURATION-3, exenatide once weekly was compared with insulin glargine (henceforth, glargine) as first injectable therapy. Here, we report the results of the final 3-year follow-up., Methods: DURATION-3 was an open-label randomised trial done between May 13, 2008, and Jan 30, 2012. Patients with type 2 diabetes aged 18 years or older were enrolled at 72 sites worldwide. They were eligible when they had suboptimum glycaemic control (HbA1c 7.1-11.0% [54-97 mmol/mol]) despite maximum tolerated doses of metformin alone or with a sulfonylurea for at least 3 months, a stable bodyweight for at least 3 months, and a BMI of 25-45 kg/m(2) (23-45 kg/m(2) in South Korea and Taiwan). Patients were randomly assigned (1:1) by computer-generated random sequence with an interactive voice-response system (block size four, stratified by country and concomitant therapy) to once-weekly exenatide (2 mg subcutaneous injection) or once-daily glargine (titrated to target) to be given in addition to their existing oral glucose-lowering regimens. The primary efficacy measure at 3 years was change in HbA1c from baseline in patients given at least one dose of the assigned drug (ie, analyses by modified intention to treat). Patients, investigators, and data analysts were not masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT00641056., Findings: 456 patients underwent randomisation and received at least one dose of the assigned drug (233 given exenatide, 223 glargine). At 3 years, least-squares mean HbA1c change was -1.01% (SE 0.07) in the exenatide group versus -0.81% (0.07) in the glargine group (least-squares mean difference -0.20%, SE 0.10, 95% CI -0.39 to -0.02; p=0.03). Transient gastrointestinal adverse events characteristic of GLP-1 receptor agonists were more frequent with exenatide than glargine (nausea: 36 [15%] of 233 patients vs five [2%] of 223; vomiting: 15 [6%] vs six [3%]; diarrhoea: 32 [14%] vs 15 [7%]), although frequency of these events did decrease after week 26 in the exenatide group. The proportion of patients who reported serious adverse events in the exenatide group (36 patients [15%]) was the same as that in the glargine group (33 [15%]). The exposure-adjusted rate of overall hypoglycaemia was three times higher in patients given glargine (0.9 events per patient per year) than in those given exenatide (0.3 events per patient per year)., Interpretation: Efficacy of once-weekly exenatide is sustained for 3 years. GLP-1 receptor agonists could be a viable long-term injectable treatment option in patients with type 2 diabetes who have not yet started taking insulin., Funding: Amylin Pharmaceuticals and Eli Lilly., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Type 2 diabetes mellitus (T2DM) is characterized by a progressive failure of pancreatic β-cell function (BCF) with insulin resistance. Once insulin over-secretion can no longer compensate for the degree of insulin resistance, hyperglycemia becomes clinically significant and deterioration of residual β-cell reserve accelerates. This pathophysiology has important therapeutic implications. Ideally, therapy should address the underlying pathology and should be started early along the spectrum of decreasing glucose tolerance in order to prevent or slow β-cell failure and reverse insulin resistance. The development of an optimal treatment strategy for each patient requires accurate diagnostic tools for evaluating the underlying state of glucose tolerance. This review focuses on the most widely used methods for measuring BCF within the context of insulin resistance and includes examples of their use in prediabetes and T2DM, with an emphasis on the most recent therapeutic options (dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists). Methods of BCF measurement include the homeostasis model assessment (HOMA); oral glucose tolerance tests, intravenous glucose tolerance tests (IVGTT), and meal tolerance tests; and the hyperglycemic clamp procedure. To provide a meaningful evaluation of BCF, it is necessary to interpret all observations within the context of insulin resistance. Therefore, this review also discusses methods utilized to quantitate insulin-dependent glucose metabolism, such as the IVGTT and the euglycemic-hyperinsulinemic clamp procedures. In addition, an example is presented of a mathematical modeling approach that can use data from BCF measurements to develop a better understanding of BCF behavior and the overall status of glucose tolerance.

Introduction: The GLP-1 receptor agonist exenatide is synthetic exendin-4, a peptide originally isolated from the salivary secretions of the Gila monster. Exenatide was developed as a first-in-class diabetes therapy, with immediate- and extended-release formulations. In preclinical diabetes models, exenatide enhanced glucose-dependent insulin secretion, suppressed inappropriately elevated glucagon secretion, slowed gastric emptying, reduced body weight, enhanced satiety, and preserved pancreatic β-cell function. In clinical trials, both exenatide formulations reduced hyperglycemia in patients with type 2 diabetes mellitus (T2DM) and were associated with weight loss., Areas Covered: This article reviews the development of exenatide from its discovery and preclinical investigations, to the elucidation of its pharmacological mechanisms of action in mammalian systems. The article also presents the pharmacokinetic profiling and toxicology studies of exenatide, as well as its validation in clinical trials., Expert Opinion: GLP-1 receptor agonists represent a new paradigm for the treatment of patients with T2DM. By leveraging incretin physiology, a natural regulatory system that coordinates oral nutrient intake with mechanisms of metabolic control, these agents address multiple core defects in the pathophysiology of T2DM. Studies have identified unique benefits including improvements in glycemic control and weight, and the potential for beneficial effects on the cardiometabolic system without the increased risk of hypoglycemia associated with insulin therapy. Peptide hormone therapeutics can offer significant advantages over small molecule drug targets when it comes to specificity, potency, and more predictable side effects. As exemplified by exenatide, injectable peptides can be important drugs for the treatment of chronic diseases, such as T2DM.

Exenatide is a glucagon-like peptide-1 receptor agonist for the treatment of type 2 diabetes and has been shown to lower blood glucose through multiple mechanisms, including glucose-dependent insulin secretion, suppression of postprandial glucagon release and slowing of gastric emptying. The effects of exenatide on biliary motility are unknown. This study evaluated the effect of a single dose of exenatide on cholecystokinin (CCK)-induced gallbladder emptying. Healthy subjects participated in this randomized, 2-period, double-blind crossover study. Fasting subjects received a single subcutaneous injection of exenatide (10 μg) or placebo 60 min before CCK infusion. Gallbladder volume and ejection fraction (EF) were assessed by ultrasonography before, during, and after CCK infusion (0.003 μg/kg infused over 50 min at 2 mL/min). The diameters of the main pancreatic duct and common bile duct were measured sonographically at the same time points before, during, and following CCK infusion. Administration of exenatide did not affect pre-CCK infusion gallbladder volume or EF compared to placebo. During the CCK-infusion, the mean minimum gallbladder volume was similar for exenatide (13.68 mL) and placebo (11.05 mL) (least squares mean [LSM] difference of 2.62 mL; 95% confidence interval [CI], -0.53, 5.78), but the mean maximum EF was lower for exenatide (28.79%) versus placebo (46.13%) (LSM difference of -17.34%; 95% CI, -30.54, -4.13). Exenatide had no clinically significant effects on pancreatic or bile duct diameters. In conclusion, exenatide reduced CCK-induced gallbladder emptying compared with placebo in fasting healthy subjects., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: Patients with type 2 diabetes mellitus are routinely treated with combinations of glucose-lowering agents. The adverse event (AE) profile and effects on glycemic control have not been assessed for the glucagon-like peptide-1 receptor agonist exenatide once weekly in combination with a thiazolidinedione (TZD) with or without metformin., Objective: This study was conducted to examine the long-term safety profile and changes in glycemic control and weight for exenatide once weekly with TZD with or without metformin in patients with type 2 diabetes mellitus over 2 years., Methods: In this single-arm, open-label trial with treatment up to 104 or 117 weeks, patients received 2 mg exenatide once weekly while continuing treatment with a TZD with or without metformin. Patients were either exenatide-naïve before this study or had previously received exenatide twice daily, which was discontinued on initiating exenatide once weekly. Patients were on a stable dosage of TZD (rosiglitazone or pioglitazone) and, if applicable, metformin. Treatment-emergent AEs were defined as those first occurring or worsening post baseline. Descriptive statistics were used for absolute and change-from-baseline data, and a one-sample t test for within-group change in glycosylated hemoglobin (HbA(1c))., Results: Of 134 patients in the intent-to-treat population (baseline mean [SD] HbA(1c),7.2% [1.0%]), 44 were exenatide-naïve (baseline HbA(1c), 7.8% [1.0%]) and 90 switched from exenatide twice daily (baseline HbA(1c), 7.0% [0.8%]). Of intent-to-treat patients, 106 (79%) completed the final treatment visit (week 104 or week 117). The most common AEs were nausea (17% of patients) and injection-site nodule (12% of patients). Serious AEs were reported in 14% of patients and 5% withdrew because of a treatment-emergent AE. No identifiable pattern of serious AEs was observed. There were 4 reports of edema and no reports of heart failure. No major hypoglycemia was reported; minor hypoglycemia was reported in 4% of patients. Exenatide-naïve patients experienced mean (SE) HbA(1c) reductions of -0.7% (0.2%) and weight reductions of -2.7 (0.8) kg, whereas patients with prior exposure to exenatide twice daily experienced a reduction of -0.4% (0.1%) in HbA(1c) and no change in weight., Conclusions: Adverse events over 2 years were consistent with the reported safety profiles of exenatide once weekly and TZDs. Exenatide-naïve patients experienced improvements in HbA(1c) and weight, while patients with the benefit of prior exenatide therapy experienced an additional reduction from baseline in HbA(1c) and no additional change in weight after 2 years. ClinicalTrials.gov identifier: NCT00753896., (Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.)

Aims: Antibody formation to therapeutic peptides is common. This analysis characterizes the time-course and cross-reactivity of anti-exenatide antibodies and potential effects on efficacy and safety., Methods: Data from intent-to-treat patients in 12 controlled (n = 2225,12-52 weeks) and 5 uncontrolled (n = 1538, up to 3 years) exenatide twice-daily (BID) trials and 4 controlled (n = 653,24-30 weeks) exenatide once weekly (QW) trials with 1 uncontrolled period (n = 128,52 weeks) were analysed., Results: Mean titres peaked early (6-22 weeks) and subsequently declined. At 30 weeks, 36.7% of exenatide BID patients were antibody-positive; 31.7% exhibited low titres (≤125) and 5.0% had higher titres (≥625). Antibody incidence declined to 16.9% (1.4% higher titre) at 3 years. Similarly, 56.8% of exenatide QW patients were antibody-positive (45.0% low/11.8% higher titre) at 24-30 weeks, declining to 45.4% positive (9.2% higher titre) at 52 weeks. Treatment-emergent anti-exenatide antibodies from a subset of patients tested did not cross-react with human GLP-1 or glucagon. Other than injection-site reactions, adverse event rates in antibody-positive and antibody-negative patients were similar. Efficacy was robust in both antibody-negative and antibody-positive patients (mean HbA1c change: -1.0 and -0.9%, respectively, exenatide BID; -1.6% and -1.3% exenatide QW). No correlation between change in HbA1c and titre was observed for exenatide BID, although mean reductions were attenuated in the small subset of patients (5%) with higher titres. A significant correlation was observed for exenatide QW with no difference between antibody-negative and low-titre patients, but an attenuated mean reduction in the subset of patients (12%) with higher titres., Conclusions: Low-titre anti-exenatide antibodies were common with exenatide treatment (32% exenatide BID, 45% exenatide QW patients), but had no apparent effect on efficacy. Higher-titre antibodies were less common (5% exenatide BID, 12% exenatide QW) and within that titre group, increasing antibody titre was associated with reduced average efficacy that was statistically significant for exenatide QW. Other than injection-site reactions, anti-exenatide antibodies did not impact the safety of exenatide., (© 2012 Blackwell Publishing Ltd.)

Objectives: To evaluate the effect of exenatide on gastric emptying (GE) in type 2 diabetes using scintigraphy., Methods: Seventeen subjects with type 2 diabetes participated in a randomized, single-blind, 3-period, crossover study. In each 5-day period, 5 or 10 microg exenatide or placebo was administered subcutaneously BID. Oral antidiabetic treatments were continued. The presence of cardiac autonomic neuropathy was assessed during screening. On day 5, after the morning dose, subjects consumed a 450-kcal breakfast containing (99m)Tc-labeled eggs and (111)In-labeled water, and GE was measured by scintigraphy. Plasma glucose and insulin, perceptions of appetite, and plasma exenatide were also quantified., Results: Exenatide slowed GE of both solid and liquid meal components [solid (T(50)(90% confidence interval [CI]); placebo, 60(50-70) min; 5 microg exenatide, 111(94-132) min; 10 microg exenatide, 169(143-201) min; both P<0.01); liquid (T(50)(90% CI), placebo, 34(25-46) min; 5 microg exenatide, 87(65-117) min; 10 microg exenatide, 114(85-154) min; both P<0.01)]. GE was not different between subjects with cardiac autonomic neuropathy (n=7), compared with those without (n=10) (P>/=0.68). Exenatide reduced postprandial glucose (area under the curve [AUC((0-6 h))]) by 69-76% and peak insulin (C(max)) by 84-86% compared with placebo. There was an inverse relationship between the postprandial rise in glucose (AUC((0-3 h))) and GE (solid T(50), r=-0.49, P<0.001)., Conclusions: Exenatide slows GE substantially in type 2 diabetes, which could be an important mechanism contributing to the beneficial effect of exenatide on postprandial glycemia.

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., (Copyright (c) 2007 Excerpta Medica, Inc.)

Aim: Exenatide, an incretin mimetic for the adjunct treatment of type 2 diabetes (DM2), reduced A1C and weight in 30-week placebo-controlled trials. This analysis examined the effects of exenatide on glycaemic control and weight over an 82-week period in patients with DM2 unable to achieve adequate glycaemic control with sulphonylurea (SU) and/or metformin (MET)., Methods: This interim analysis is of 314 patients who received exenatide in the 30-week placebo-controlled trials and subsequently in 52 weeks of open-label uncontrolled extension studies for 82 weeks of exenatide in total. Patients continued their SU and/or MET regimens throughout., Results: Patients completed 82 weeks of exenatide treatment [n = 314, 63% M, age 56 +/- 10 years, weight 99 +/- 21 kg, body mass index 34 +/- 6 kg/m2, A1C 8.3 +/- 1.0% (mean +/- SD)]. Reduction in A1C from baseline to week 30 [-0.9 +/- 0.1% (mean +/- SE)] was sustained to week 82 (-1.1 +/- 0.1%), with 48% of patients achieving A1C < or = 7% at week 82. At week 30, exenatide reduced body weight (a secondary endpoint) from baseline (-2.1 +/- 0.2 kg), with progressive reduction at week 82 (-4.4 +/- 0.3 kg). Similar results were observed for the intent-to-treat population (n = 551), with reductions in A1C and weight at week 82 of -0.8 +/- 0.1% and -3.5 +/- 0.2 kg respectively. The 82-week completer cohort showed statistically significant improvement in some cardiovascular risk factors. The most frequent adverse events were generally mild-to-moderate nausea and hypoglycaemia., Conclusion: In summary, 82 weeks of adjunctive exenatide treatment in patients with DM2 treated with SU and/or MET resulted in sustained reduction in A1C and progressive reduction in weight, as well as improvement in some cardiovascular risk factors.

Aims: Exenatide is an incretin mimetic whose effect on glycaemic control in patients with Type 2 diabetes is currently under investigation. This study assessed the effect of injection time relative to a standardized meal on postprandial pharmacodynamics of exenatide in patients with Type 2 diabetes., Methods: Eighteen patients participated in this single-centre, open-label, placebo-controlled, randomized, six-way crossover study. Patients received subcutaneous injections of either placebo (-15 min) or 10 microg of exenatide at -60, -15, 0, +30 or +60 min relative to a standardized breakfast meal on six consecutive days. Serial blood samples were assayed for plasma glucose and insulin concentrations., Results: For all exenatide treatments, incremental postprandial glucose area under the postprandial plasma glucose curve from zero to 6 h (AUC0-6 h) was significantly reduced compared with placebo. When exenatide was administered before (-60, -15 min) or with the meal (0 min), peak postprandial glucose concentrations were significantly decreased (P < 0.0001 for all treatments) compared with placebo. Post-meal exenatide administration (+30, P < 0.05; +60 min, P = 0.21) resulted in smaller peak glucose reductions and in some patients transient low plasma glucose concentrations were reported. Peak plasma insulin concentrations in the pre-meal treatments were significantly lower than placebo (P < 0.05 for all treatments), while post-meal dosing groups exhibited a trend towards higher insulin peaks compared with placebo. The most common adverse events related to exenatide were headache, nausea, dyspepsia and vomiting, and were generally of mild-to-moderate intensity., Conclusions: In this study, all exenatide treatments demonstrated reductions in postprandial plasma glucose excursions compared with placebo. Pre-meal and with meal administration of exenatide produced greater reduction of postprandial glucose excursions compared with post-meal administration. These data support flexible dosing of exenatide at any time within 60 min before a meal.

This study assessed the safety profile and efficacy of a new combination therapy (insulin lispro plus sulfonylurea) in patients with type 2 diabetes mellitus experiencing secondary oral agent failure. A total of 423 patients were randomly assigned to 3 treatment groups: preprandial insulin lispro plus sulfonylurea (L + S), bedtime neutral protamine Hagedorn (NPH) insulin plus sulfonylurea (N + S), and preprandial insulin lispro plus bedtime NPH insulin (L + N). Mean decreases in glycosylated hemoglobin from baseline were 1.60%+/-1.27% for patients receiving L + S, 1.21%+/-1.21% for those receiving N + S, and 1.40%+/-1.46% for those receiving L + N (within treatment, P<0.001; for L + S vs. N + S, P = 0.003). Fasting blood glucose level was higher in patients receiving L + S (171+/-46.5 mg/dL) or L + N (166+/-52.5 mg/dL) than in those receiving N + S (144+/-48.2 mg/dL) (P<0.001, for both comparisons). Conversely, postprandial blood glucose level was lower in patients receiving L + S (165+/-41.6 mg/dL) or L + N (165+/-46.3 mg/dL) than in those receiving N + S (213+/-58.3 mg/dL) (P<0.001, for both comparisons). The overall rate of hypoglycemia (episodes per 30 days) was not statistically significant when the L + S, N + S, and L + N therapies were compared (0.99+/-1.74 vs. 0.87+/-2.31 vs. 1.16+/-2.38, respectively). The rate of nocturnal hypoglycemia was lowest in the L + S group (0.00+/-0.00 vs. 0.10+/-0.37 for the N + S group vs. 0.15+/-0.54 for the L + N group; P = 0.004). L + S, which has a safety profile equal to those of N + S and L + N, is an effective treatment for patients with type 2 diabetes who experience oral sulfonylurea agent failure. L + S offers an alternative to these established combination therapies in patients whose type 2 diabetes cannot be controlled with a sulfonylurea alone.

The absorption of regular human insulin from subcutaneous injection sites is delayed due to the self-association of insulin to multimeric forms. The insulin analogue insulin lispro has a weak self-association and a fast absorption rate. We examined the safety and efficacy of insulin lispro in the premeal treatment of patients with diabetes mellitus. A 12-month study was performed in 336 patients with insulin-dependent diabetes mellitus (IDDM) and 295 patients with non-insulin-dependent diabetes mellitus (NIDDM). The patients were randomized to inject either regular human insulin 30 to 45 minutes before eating, or insulin lispro immediately before each meal, in addition to basal insulin. The postprandial rise in serum glucose was lower in patients receiving insulin lispro than in those receiving regular human insulin therapy. At end point the increment was significantly lower at 1 hour (35%) and at 2 hours (64%) after the meal in IDDM patients; in NIDDM patients, the increment was nonsignificantly lower at 1 hour (19%) and significantly lower at 2 hours (48%). IDDM patients receiving insulin lispro achieved significantly lower glycated hemoglobin (HbA1c) levels in patients receiving regular human insulin (8.1% vs 8.3%). In NIDDM patients, HbA1c levels decreased equally in both treatment groups. Due to its fast absorption rate, insulin lispro improves postprandial control in diabetes. Insulin lispro can be considered one step toward optimal insulin therapy and improved patient convenience.

The time-action profile of the insulin analogue insulin lispro ([Lys(B28), Pro(B29)] human insulin) with its rapid onset and short duration of action might be more suitable to limit hyperglycaemic excursions after a meal rich in rapidly absorbable carbohydrates in comparison to regular human insulin. A randomized, double-blind study was performed in 10 Type I diabetic patients with good metabolic control (HbA1c 7.0 +/- 0.5%). After a baseline period of 3 h (blood glucose clamped at 6.7 mmol l-1, i.v. insulin infusion of 0.2 mU kg-1 min-1 throughout the study), the patients ate a pizza, drank a cola and had a carbohydrate-rich dessert (total carbohydrate content 140 g). Immediately before the meal 15.4 +/- 3.5 U of either insulin preparation were injected subcutaneously. Blood glucose concentrations were monitored continuously thereafter. Following the injection of insulin lispro the area under the blood glucose curve after the meal was 78% of that of regular insulin (1.76 +/- 0.34 vs 2.26 +/- 0.68 mol l-1 *240 min-1; p < 0.01). Maximal blood glucose excursions were higher and were reached later after regular insulin as compared to insulin lispro (11.9 +/- 2.8 vs 9.9 +/- 1.4 mmol l-1; p < 0.05; 66 +/- 37 vs 41 +/- 7 min; p < 0.05). Maximal individual differences in the blood glucose excursions (regular human insulin minus insulin lispro) were 4.8 +/- 2.2 mmol l-1 (p < 0.0001 against zero) after 110 +/- 37 min. In Type 1 diabetic patients prandial blood glucose excursions after a carbohydrate rich meal were reduced after preprandial injection of insulin lispro in comparison to human regular insulin.

Antiproliferative treatment of patients with metastatic endocrine gastroenteropancreatic tumours (GEP) is based mainly on chemotherapeutic protocols whereby drug toxicity is a major handicap. Octreotide is the first choice in the control of hormone mediated symptoms. From retrospective and a few prospective studies it has been suggested that octreotide exhibits antiproliferative properties. The prospective German Sandostatin multicentre phase II trial investigated the effects of 200 micrograms octreotide thrice daily for one year on tumour growth and endocrine abnormalities in 103 patients. Octreotide treatment was continued in those patients responding to the drug until tumour progression occurred. In 28 of those with tumour progression during 200 micrograms thrice daily octreotide dose was increased to 500 micrograms thrice daily. The study sample consisted of 52 patients with computed tomography confirmed tumour progression and 13 patients with stable disease before octreotide treatment, whereas no preobservation period was available in 38 patients. Nineteen patients (36.5%) with computed tomography confirmed tumour progression experienced stabilisation of tumour growth lasting for at least three months. Median duration of stable disease was 18 months. At month 12, stable disease continued in 12 patients, declined after 24 months to nine patients, and after 36 months to five patients. Tumour regression has not been seen in this or other subgroups. In the subgroup with stable disease before octreotide, stable disease continued in 53.8% of patients over 12 months. Increase of octreotide dose to 500 micrograms thrice daily did not influence progression seen during the lower dose with the exception of one patient in whom tumour progression changed to stable disease. No association of tumour size response and patients' characteristics could be detected. The results suggest that octreotide inhibits tumour growth in patients with metastasised endocrine GEP tumours. The antiproliferative effect is, at least in some patients, longlasting. Currently, octreotide can only be recommended as an antiproliferative drug if patients with clearly progressive disease show stabilisation after treatment for three to six months.

In a randomized, open-label, controlled cross-over trial, 107 patients with type 1 diabetes were treated with either regular human insulin or insulin lispro, a rapid-acting insulin analogue. After a lead-in period of 2 to 4 weeks, the patients were randomized to receive intensified insulin treatment with one of the insulins. NPH-human insulin was used for basal substitution in both groups. The crossover took place after 3 months of treatment. Efficacy and safety of the drugs were established by the assessment of hemoglobin A1c, pretest blood glucose, 1 and 2-hour postprandial glucose excursions, number of hypoglycemic episodes, daily insulin doses, body weight, insulin antibodies, and the number and severity of adverse events. A questionnaire comprised of four primary domains was used to measure some quality of life aspects of the patients. Both treatment regimens were well tolerated. While no differences were seen in the hemoglobin A1c values, there was a trend for a decrease in the pretest blood glucose levels and significant decreases of the 1 and 2-hour postprandial glucose excursions in the patients treated with insulin lispro. The number of hypoglycemic episodes was also significantly lower in the insulin lispro treatment period. The evaluation of the quality of life questionnaire revealed an improvement in the patients treatment satisfaction for the insulin lispro group. During treatment with insulin lispro, the basal insulin doses increased slightly. However, the total daily insulin doses decreased to a greater extent with insulin lispro as compared to regular human insulin. Human insulin-specific antibody binding values at endpoint were not different for the two treatments. In conclusion, intensive insulin treatment with insulin lispro therapy results in improved postprandial glycemic control and HbA1c levels at least equal to the treatment with regular human insulin but with less hypoglycemia and more treatment satisfaction for the patient.

The differentiating agent sodium butyrate inhibits proliferation and stimulates cell-specific hormone expression in rat insulinoma cells. In this study, we investigated the effect of sodium butyrate on neuroendocrine cytodifferentiation in the rat insulinoma subclone, RINm5F. The cells were cultured with 0.5, 1, or 1.5 mM sodium butyrate for up to 72 h. Ultrastructurally, cells cultured with 1 mM sodium butyrate revealed a more differentiated appearance with an induction of cellular compartments involved in regulated insulin secretion. Morphometric analysis showed a significant elevation of neuroendocrine granule density. The total area of the specific granules was increased after incubation with 1 mM sodium butyrate for 48 and 72 h. Proliferation of RINm5F cells was inhibited by sodium butyrate in a dose-dependent manner. DNA production ceased completely within 24 h at 1.5 mM sodium butyrate. This concentration of sodium butyrate increased the cellular insulin content 8.9-fold and the insulin production 2-fold after 72 h. The insulin release was reduced from 79 +/- 3.5% in controls to 37 +/- 5.6% of total in a 24-h incubation period after 3 days of culture with 1.5 mM sodium butyrate. Insulin mRNA levels increased to a maximum of 324% compared with controls after 48 h of culture with 1.5 mM sodium butyrate. Chromogranin A mRNA levels increased to a similar extent (368 +/- 26%), whereas sodium butyrate did not stimulate the expression of synaptophysin, a major membrane component of small neuroendocrine vesicles. In conclusion, our data suggest the selective induction of neuroendocrine cytodifferentiation by sodium butyrate in RINm5F cells.(ABSTRACT TRUNCATED AT 250 WORDS)

In the serum of patients with malignant endocrine gastroenteropancreatic (GEP) tumours, both alpha-subunit (alpha-SU), common to all glycoprotein hormones, as well as free beta-subunit of human chorionic gonadotropin (hCG-beta) have been reported to be elevated in a substantial fraction. Both have been discussed as markers of malignancy in these neoplasms. In the present study we evaluated the diagnostic significance of alpha-SU and hCG-beta as serum markers in patients with malignant endocrine gastroenteropancreatic tumours. The study group consisted of 52 patients with endocrine GEP-malignancies (24 nonfunctioning, 23 carcinoid syndromes, four gastrinoma, one glucagonoma), located in the small intestine (n = 29), pancreas (n = 17), colon or rectum (n = 3), retroperitoneum (n = 2) and stomach (n = 1). alpha-SU and hCG-beta immunoreactivity was also assessed in the serum of patients with benign GEP-tumors (five insulinoma, and three gastrinoma). Concentrations of alpha-SU and hCG-beta were determined using two highly sensitive and specific immunoradiometric assays employing two monoclonal antibodies each. In 19 of 52 patients (37%), either alpha-SU (n = 9), hCG-beta (n = 7) or both subunits (n = 3) were elevated. In the subgroup of 24 patients with nonfunctioning GEP-tumours, increased concentrations of either alpha-SU (n = 6) or hCG-beta(n = 3) or both subunits (n = 1) were found in 10 of 24 patients (42%). In four of 23 patients with carcinoid syndrome (17%), either alpha-SU (n = 2), hCG-beta(n = 1) or both subunits (n = 1) were above the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Receptor scintigraphy with 111In-pentetreotide is a complementary imaging technique with a sensitivity of 88% for the localization of the primary tumor and its metastases in patients presenting with the clinical and biochemical symptoms of an endocrine tumor of the gastrointestinal tract or the pancreas. As a whole-body scintigraphic technique it covers all body regions and is also able to reveal small tumors which can only be detected with difficulty or not at all by the usual imaging methods. In 104 patients with GEP tumors or after operative removal of such tumors, receptor scintigraphy proved to be superior to ultrasound and computed tomography in 34%, equal in 52% and inferior in 14% of the cases.

Objective: The purpose of this study was to determine the value of somatostatin-receptor scintigraphy (SRS) in the preoperative localization of gastrointestinal endocrine tumors. The authors report their preliminary experiences with this new technique as compared to conventional imaging studies like computed tomography (CT) and ultrasonography (US)., Summary Background Data: Most endocrine tumors possess high-affinity somatostatin-receptors. Using the stable, 111Indium labelled somatostatin analogue pentatreotid, which binds to these receptors, it is possible to detect somatostatin-receptor-positive tumors scintigraphically., Methods: In nine patients with various gastrointestinal endocrine tumors, SRS, CT, and US were performed before surgical exploration. The preoperative imaging studies and intraoperative ultrasound (IOUS) were then compared to findings on surgical exploration., Results: Twelve primary tumors were found in 8 patients at surgical exploration. These primary tumors were correctly identified with SRS in five patients, with US in four patients, and with CT in three patients. In one patient with the Zollinger-Ellison syndrome, scintigraphy suggested a tumor in the area of the hepatoduodenal ligament, while CT and US had negative results. The underlying gastrinoma could not be identified despite extensive surgical exploration. Scintigraphy, CT, and US showed comparable results in the detection of metastases in four patients., Conclusions: The data from this small series suggest that SRS is helpful in the preoperative localization of gastrointestinal endocrine tumors.

A prospective study was performed to determine the efficacy of octreotide (Sandostatin; SMS 201-995) 200 micrograms tid in controlling tumor growth. The study included 21 patients with metastasized endocrine GEP tumors: 6 gastrinomas, 8 carcinoid syndromes, 7 nonfunctioning tumors. Treatment was performed for 3 to 59 months (median 15 months). Evaluation of the response to octreotide was facilitated in 12 patients by a pretreatment observation period of 3 to 47 months (median 17 months) during which the natural growth behavior was determined. Based on the presence or absence of a control period prior to treatment, 5 patients were considered to be responders, 7 as questionable responders (no pretreatment phase available), and 9 as nonresponders. None of the 21 patients had documented shrinkage of the tumor mass. The most favorable response was tumor standstill. In all but one responder an escape to an initially favorable response occurred after 6 to 28 months (median 14 months). Proved inhibition of growth was paralleled by a reduction of serum and urine hormone parameters, whereas unaltered progression of tumor growth was observed also in the presence of hormone suppression. Tumor growth and hormone release was inhibited in the absence and presence of somatostatin receptors on the tumor. It is concluded that octreotide exerts a limited effect on metastatic GEP tumor growth. The evaluation of a response to octreotide is facilitated by an observation period prior to the drug that provides information on growth characteristics of the tumor. The presence of octreotide receptors does not predict the success of therapy.

Amylin was isolated from human insulinomas, but there has been only preliminary data regarding whether this peptide can also be detected in other types of gastroenteropancreatic endocrine tumors. In the present study, immunohistochemical staining of 87 gastroenteropancreatic endocrine tumors demonstrated amylin immunoreactivity in 21.8% of the neoplasmas. Thirteen of 15 insulinomas, three of 21 gastrinomas, two of 29 nonfunctioning tumors, and one of 18 carcinoids were amylin-immunoreactive. Seventeen of the 19 amylin-immunoreactive tumors were primarily located in the pancreas, but two tumors were found in the intestine. Measurements of amylin messenger RNA expression in a few tumors revealed amylin synthesis in these tumors. Amylin immunoreactivity did not correlate with invasion and metastasis. However, the rate of curative resections was significantly higher in amylin-immunoreactive tumors. These results demonstrate for the first time that amylin immunoreactivity is not restricted to insulinomas and can also occur rarely in endocrine tumors of the intestine.

Between 1987 and 1991, 16 patients (13 females, three males; mean age 52.4 [33-73] years) with Zollinger-Ellison syndrome (ZES) were treated according to a standardized surgical concept. The diagnostic work-up consisted of measuring serum gastrin levels, pre-operative localization by ultrasound and abdominal computed tomography, as well as extensive staging by laparotomy. As complete a tumour resection as possible was the aim of treatment in 15 patients, while in one patient it was to reduce the tumour mass. In six patients who had resection of a solitary tumour there was no evidence of recurrence after 6-42 months of follow-up. Exploration of the duodenum made it possible to identify and then remove a small gastrinoma of the duodenal wall in three patients. No gastrinoma was found in one patient despite extensive exploration. In a further four patients the laparotomy was purely exploratory, because diffuse metastasization was found. In four patients the primary tumour and, where present, the regional lymph nodes were removed, but the signs of ZES persisted, i.e. the intervention was merely palliative. In one female patient, reduction of tumour mass was necessary because the symptoms could not be controlled by conservative measures: she died postoperatively from toxic hepatitis. This experience indicates that standardized surgical intervention achieves potentially curative results in nearly 40% of patients. Including the duodenum in the surgical exploration allows the identification of even small gastrinomas of the duodenal wall. It is concluded that all patients with ZES but no evidence of diffuse metastases should undergo surgical treatment.

One hundred and fifteen gastroenteropancreatic (GEP) patients with malignant endocrine tumours entered a prospective multicentre trial (12 patients with gastrinoma, 53 with carcinoid syndrome, 45 with nonfunctioning tumours and 5 with other endocrine GEP tumours) to determine the efficacy of 200 micrograms Sandostatin t.i.d. in the control of tumour growth. This interim report describes the results in 85 patients. Thirty-four patients died, 14 before and 20 after the first follow-up investigation, indicating a 'negative' selection of patients included in the trial and suggesting that Sandostatin is unable to prevent disease progression when it is far advanced. In the evaluation of 68 patients followed up for at least 3 months, partial regression was observed in 4.4%, stable disease in 50% and tumour progression in 45%. An initially favourable response occurred frequently, however, it was followed by a decrease in response, from 54.4% at 3 months to 38% at 12 months, for the whole group of patients. Proven inhibition of tumour growth was mirrored by suppression of serum and urine hormone parameters. It is concluded that Sandostatin exerts a beneficial effect on tumour growth in patients with metastatic endocrine GEP tumours. This beneficial effect decreases with time and is as yet unpredictable in the individual patient.

The value of silver staining of nucleolar organizer regions (AgNORs) and human chorionic gonadotropin alpha-chain reaction (HCG-alpha) as markers of malignancy was investigated in 60 primary pancreatic endocrine tumours, 37 of which had metastasized at the time of surgery, and in one of which metastases developed 4 years after surgery. Assessment of AgNORs by digital image analysis revealed few but large AgNORs (mean number 2.5 +/- 1.1; mean area 0.32 +/- 0.1 microns 2) in the 22 benign tumours and many but small AgNORs (mean number 5.1 +/- 1.9, P < 0.05; mean area 0.18 +/- 0.09 microns 2, P < 0.01) in the malignant tumours. Quantification of the number of AgNORs per tumour cell nucleolus (AgNOR distribution score) showed that 96% (26/27) of tumours exhibiting at least 5% of cells with more than six AgNORs per nucleolus showed metastases either at the time of diagnosis or up to 4 years after surgery. HCG-alpha immunoreactive cells were present in 25/38 (66%) malignant tumours and in 4/22 (18%) benign tumours. Combined evaluation of AgNOR distribution and HCG-alpha scores showed a high positive predictive value of 96% in cases with a raised AgNOR distribution score irrespective of the HCG-alpha status. A good negative predictive value (81%) was, however, only obtained if both parameters, AgNOR distribution and HCG-alpha scores, were negative. Thus, investigation of AgNORs and HCG-alpha is helpful in predicting malignancy in a high percentage of pancreatic endocrine tumours.