Aims/hypothesis Glucose-dependent insulinotropic polypeptide (GIP) and xenin, regulatory gut hormones secreted from enteroendocrine K cells, exert important effects on metabolism. In addition, xenin potentiates the biological actions of GIP. The present study assessed the actions and therapeutic utility of a (DAla 2 )GIP/xenin-8-Gln hybrid peptide, in comparison with the parent peptides (DAla 2 )GIP and xenin-8-Gln. Methods Following confirmation of enzymatic stability, insulin secretory activity of (DAla 2 )GIP/xenin-8-Gln was assessed in BRIN-BD11 beta cells. Acute and persistent glucose-lowering and insulin-releasing effects were then examined in vivo. Finally, the metabolic benefits of twice daily injection of (DAla 2 )GIP/xenin-8-Gln was determined in high-fat-fed mice.