Liposomes in oral delivery: mechanisms, advances, challenges, and future perspectives

Oral liposome drug delivery system has gained attention due to their potential to improve patient compliance, enhance the bioavailability of encapsulated poorly soluble drugs, and protect drugs from gastrointestinal degradation. Liposomes structurally mimic the human cell membrane, and so are biocompatible and facilitate interactions with cell membranes. However, liposome drug delivery remains inherently challenging due to limitations such as physicochemical instability, limited permeability across GI barriers, and manufacturing scalability constraints. This review first summarizes the current innovative oral liposome products such as Meriva^®, Lipicur, and silymarin liposomes. This is followed by a comprehensive overview of the biological barriers for liposome absorption. The report further reviews current understanding the mechanisms for liposomes to cross the GI track and enter the bloodstream, including cellular uptake, transepithelial transport, and lymphatic transport. Formulation strategies to improve absorption such as lipid composition, surface modification techniques such as PEGylation and chitosan are discussed. Understanding these properties is essential for enhancing transepithelial transport efficiency and designing effective oral liposome delivery systems. Finally, the recent development in manufacturing scalability is also covered. Owing to their favorable properties, oral liposome delivery systems remain an active area for innovations in expanding their applications. It is anticipated that demand for oral liposomal drug‑delivery systems will continue to grow, driven by the rising prevalence of chronic diseases that require long‑term therapeutic management.