screening; body mass index (BMI) < 23 kg/m2 or > 40 kg/m2
;
non-stable medical conditions, recent active infections,
active gastrointestinal disease, or prior bariatric surgery;
estimated GFR < 60 mL/min/1.73 m2
; or alanine aminotransferase
> 1.5 times the upper limit of normal.
The study protocol and amendment were approved by the
Sterling Institutional Review Board, which served as the
study’s central Institutional Review Board, and the study
was conducted in accordance with the ethical principles that
have their origin in the Declaration of Helsinki and that are
consistent with Good Clinical Practices and applicable regulatory
requirements. All patients provided written informed
consent prior to participation.
2.2. Randomization and treatments
During the double-blind treatment phase, patients were
admitted to the clinical research center during each of four
treatment periods. Careful attention was paid to maintaining
stable glycemic control throughout the four periods,
and matching meals and activity during each of the inpatient
stays. Patients were randomized to one of four treatment
sequences based on a computer-generated randomization
schedule prepared by the study sponsor; randomization was
balanced using randomly permuted blocks and stratified by
study site. Each period lasted 3 days, during which patients