Variability in and predictors of glycaemic responses after 24 weeks of treatment with exenatide twice daily and exenatide once weekly

The range of glycated haemoglobin (HbA1c) responses and characteristics associated with above-average response to exenatide twice daily and once weekly were examined. Data were pooled from 8 exenatide-twice-daily and 5 exenatide-once-weekly studies. A baseline HbA1c-corrected measure of change in HbA1c after 24 weeks identified high, average and low responses. Multiple linear regression and multivariate generalized estimating equation models identified factors associated with high response. Among 2355 participants (exenatide twice daily, n = 1414; exenatide once weekly, n = 941), baseline HbA1c correlated with change in HbA1c (P < .0001). Across baseline HbA1c levels, the 25th to 75th percentile of HbA1c change ranged from -0.3% to -3.2% with exenatide twice daily and from -0.5% to -3.6% with exenatide once weekly. Asian ethnicity and older age were significantly associated with high response to exenatide twice daily; no factors were significantly associated with response to exenatide once weekly. These data provide clinically useful information for estimating the likelihood that, depending on baseline HbA1c, an individual can achieve HbA1c goals. The association between Asian ethnicity, age and high response to exenatide twice daily may relate to the specific effects of exenatide twice daily on postprandial glucose.