A brief overview of quality by design approach for developing pharmaceutical liposomes as nano-sized parenteral drug delivery systems

Liposomes are sophisticated drug delivery vehicles that have significantly broadened the range of therapeutic agents that can be selectively delivered along with controlled release. Liposomes are small vesicles (size optimizable) composed of a lipid bilayer that encapsulates hydrophilic as well as hydrophobic drugs. This advancement has led to the creation of liposomal nano-formulations for drugs with very poor water solubility and cell membrane permeability, resulting in improved therapeutic efficacy and reduced side effects. Liposomal formulations can also be engineered with ligands or antibodies to target specific cells or tissues, ensuring site-specific drug delivery and minimizing off-target side effects. These targeted liposomal formulations have shown promising potential in treating various diseases, such as cancer, infectious diseases, and inflammatory disorders. With continuous advancements in liposomal technology, researchers are exploring new ways to further optimize the liposomal formulations for enhanced drug stability, bioavailability, and targeted delivery to specific cells or tissues. The Quality by Design (QbD) approach is a systematic and scientific method for designing and developing pharmaceutical products, ensuring quality and consistency throughout the product lifecycle. Applied to the development of pharmaceutical liposomes, QbD facilitates the optimization of liposome formulations for targeted drug delivery, improved stability, and enhanced therapeutic outcomes. The creation of novel liposomal formulations with superior drug stability, bioavailability, and targeting capabilities will undoubtedly play a crucial role in shaping the future of medicine and improving patient care. This brief review provides an overview of the development of liposomes as nanocarrier systems for parenteral drug delivery, covering aspects such as quality manufacturing attributes, structure, preparation methods, characterization, clinical applications, and regulatory considerations.