Disclosed are PEGylated modifications of Exendin 4 analogs and uses thereof. In particular disclosed are PEGylated modifications of Exendin 4 analogs as shown in formula (I) i.e. PEG M X (Ex 4) or pharmaceutically acceptable salts thereof as well as Exendin 4 analogs as shown in formula (II) i.e. [Aa]Exendin 4 wherein the symbols are as defined in the specification. Further disclosed are methods for preparing the PEGylated modifications uses thereof compositions comprising same as well as use of the Exendin 4 analogs in the preparation of the PEGylated modifications. In the PEGylated modifications modification by polyethylene glycol specifically occurs locally in the peptide chains of the Exendin 4 analogs. The PEGylated modifications can be used to prevent and/or treat diseases and/or symptoms related to decreased activity of GLP 1 receptors such as type II diabetes.
