Exenatide effects on diabetes, obesity, cardiovascular risk factors and hepatic biomarkers in patients with type 2 diabetes treated for at least 3 years.
BACKGROUND
Exenatide, an incretin mimetic for adjunctive treatment of type 2 diabetes (T2DM), reduced hemoglobin A(1c) (A1C) and weight in clinical trials. The objective of this study was to evaluate the effects of > or = 3 years exenatide therapy on glycemic control, body weight, cardiometabolic markers, and safety.


METHODS
Patients from three placebo-controlled trials and their open-label extensions were enrolled into one open-ended, open-label clinical trial. Patients were randomized to twice daily (BID) placebo, 5 mug exenatide, or 10 mug exenatide for 30 weeks, followed by 5 mug exenatide BID for 4 weeks, then 10 mug exenatide BID for > or = 3 years of exenatide exposure. Patients continued metformin and/or sulfonylureas.


RESULTS
217 patients (64% male, age 58 +/- 10 years, weight 99 +/- 18 kg, BMI 34 +/- 5 kg/m(2), A1C 8.2 +/- 1.0% [mean +/- SD]) completed 3 years of exenatide exposure. Reductions in A1C from baseline to week 12 (-1.1 +/- 0.1% [mean +/- SEM]) were sustained to 3 years (-1.0 +/- 0.1%; p < 0.0001), with 46% achieving A1C < or = 7%. Exenatide progressively reduced body weight from baseline (-5.3 +/- 0.4 kg at 3 years; p < 0.0001). Patients with elevated serum alanine aminotransferase (ALT) at baseline (n = 116) had reduced ALT (-10.4 +/- 1.5 IU/L; p < 0.0001) and 41% achieved normal ALT. Patients with elevated ALT at baseline tended to lose more weight than patients with normal ALT at baseline (-6.1 +/- 0.6 kg vs. -4.4 +/- 0.5 kg; p = 0.03), however weight change was minimally correlated with baseline ALT (r = -0.01) or ALT change (r = 0.31). Homeostasis Model Assessment B (HOMA-B), blood pressure, and aspartate aminotransferase (AST) all improved. A subset achieved 3.5 years of exenatide exposure and had serum lipids available for analysis (n = 151). Triglycerides decreased 12% (p = 0.0003), total cholesterol decreased 5% (p = 0.0007), LDL-C decreased 6% (p < 0.0001), and HDL-C increased 24% (p < 0.0001). Exenatide was generally well tolerated. The most frequent adverse event was mild-to-moderate nausea. The main limitation of this study is the open-label, uncontrolled nature of the study design which does not provide a placebo group for comparison.


CONCLUSIONS
Adjunctive exenatide treatment for > or = 3 years in T2DM patients resulted in sustained improvements in glycemic control, cardiovascular risk factors, and hepatic biomarkers, coupled with progressive weight reduction.
Klonoff
David C
DC
Diabetes Research Institute, Mills-Peninsula Health Services, San Mateo, CA, USA.
Buse
John B
JB
Nielsen
Loretta L
LL
Guan
Xuesong
X
Bowlus
Christopher L
CL
Holcombe
John H
JH
Wintle
Matthew E
ME
Maggs
David G
DG
D000368:Aged; D054316:Biomarkers, Pharmacological / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002318:Cardiovascular Diseases / Q000209:etiology* / Q000517:prevention & control; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D000077270:Exenatide; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000209:etiology* / Q000517:prevention & control; D010455:Peptides / Q000494:pharmacology* / Q000627:therapeutic use*; D010919:Placebos; D012307:Risk Factors; D013997:Time Factors; D014688:Venoms / Q000494:pharmacology* / Q000627:therapeutic use*
D054316:Biomarkers, Pharmacological; D000077270:Exenatide; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D010455:Peptides; D010919:Placebos; D014688:Venoms; C517652:hemoglobin A1c protein, human