Liposomal antimicrobials in the fight against bacterial and fungal pathogens: clinical successes, development challenges, and future perspectives

Bacterial, fungal, and protozoan infections pose a rapidly escalating threat to global health, exacerbated by the rise in antimicrobial resistance. Current therapies against microbial pathogens are limited by high systemic toxicity and poor drug solubility. Liposomal formulations (spherical vesicles composed of lipid bilayers) have demonstrated remarkable clinical potential in addressing these concerns, as evidenced by the marketed products AmBisome® and Arikayce®. These products, which deliver amphotericin B via parenteral injection and amikacin via inhalation, exemplify how liposomes effectively mitigate drug-associated toxicity, enhance therapeutic efficacy, and overcome the biological barriers inherent to infection sites, including complex microbial biofilms, mucosal interfaces, or the blood–brain barrier. Complementary insights from anticancer research indicate that strategic manipulation of liposomal composition and structure can enhance their therapeutic potential. Adjustments in lipid charge, fluidity, and PEGylation, in particular, highlight their versatility and broad applicability for antimicrobial drug delivery. Liposomal antimicrobials can modulate pharmacokinetic profiles, achieve targeted release at sites of infection, and increase local drug concentrations, which are key advantages over conventional treatments. Despite these therapeutic advances, successful clinical translation and widespread adoption of liposomal antimicrobials remain highly dependent on overcoming existing technological and manufacturing challenges. This review emphasises the need for a paradigm shift within liposomal antimicrobial development, encouraging progression from initial research and development toward scalable, reproducible, and economically viable commercial manufacturing platforms. This transition is essential not only for ensuring the global accessibility and affordability of existing therapies but also for expanding the development of clinically relevant liposomal antimicrobial nanomedicines.