The present invention relates to a long acting composition comprising, therapeutically effective amount of liraglutide, a block or a graft copolymer comprising hydrophilic and hydrophobic moieties or mixtures thereof, at least one amphipath, and an aqueous vehicle, wherein the composition is in the form of a gel which is rendered injectable when forced through a needle by means of a plunger. The composition provides effective blood glucose control for about 6 days to about 14 days after single administration to a subject in need thereof, in particularly for about a week.