I would like to offer a clarification regarding information included in Table 1 (p. 149) of my recent article. The data cited in the first row summarize the range of lowering of A1C, fasting plasma glucose, and postprandial glucose observed with the GLP-1 receptor agonists twice-daily exenatide, once-weekly exenatide, and once-daily liraglutide. These data come from the phase 3 clinical trials.15 

It was not intended, and it should not be inferred, that the data summarized in Table 1 provide a relative comparison of the effects of the three GLP-1 receptor agonists on these three glycemic endpoints. Comparison of the glycemic effects can be discerned only from the results of each of the five trials; each provides a head-to-head comparison of two of the three GLP-1 receptor agonists. Comparisons between studies are not possible because of differences in study design, patient inclusion and exclusion criteria, and treatment regimens. The results of the five trials are described in the body of my article on the same page as the table.

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