Intramuscular injection of palmitic acid-conjugated Exendin-4 loaded multivesicular liposomes for long-acting and improving in-situ stability

Background Exendin-4 (Ex4) is a promising drug for diabetes mellitus with a half-life of 2.4 h in human bodies. Besides, the E×4formulations currently employed in the clinic or under development have problems pertaining to stability. In this study, palmitic acid-modified E×4(Pal-Ex4) was prepared and purified to extend the half-life of Ex4. In addition, Pal-Ex4-MVLs were further designed and optimized as a long-acting delivery system for intramuscular injection.