In subjects with poorly controlled diabetes, exenatide was associated with a reduction in HbA(1c) that was similar to introducing another oral agent or insulin. Weight loss may be an advantage with exenatide. Long-term studies in diverse and unselected populations are needed to clarify the benefit vs. harm profile of this drug.

The CYP2D6*4 allele is not associated with earlier PD onset. *4 May be associated with survival. Inconsistent results from allelic association studies may have been due to an unrecognized age effect.