Supramolecular lipidic drug delivery systems: From laboratory to clinic - A review of the recently introduced commercial liposomal and lipid-based formulations of Amphotericin B

The developmental work, mode of action and pharmacokinetics, and the clinical efficacy and safety, of the three recently introduced liposomal and lipid-based formulations of amphotericin B, i.e. AmBisome(TM); Abelcet(TM) and Amphocil(TM), have been reviewed. The three formulations, all of which have markedly improved the therapeutic profile of this drug, exhibit striking differences: in their morphology: AmBisome(TM) forms small unilamellar vesicles (SW) of 50-100 nm diameter; Abelcet(TM) (Amphotericin B Lipid Complex, ABLC) forms ribbon-like structures having a diameter in the 2-5 mu m range; and Amphocil(TM) (Amphotericin B Colloidal Dispersion, ABCD) forms disc-shaped particles of 122 nm diameter and 4 nm thickness. The pharmacokinetics of the differing formulations are quite diverse, reflecting their different morphologies. The altered biodistribution of the drug caused by its association with a lipidic carrier plays an integral role in reducing drug toxicity. The commercial introduction of these formulations represents a significant milestone in the history of liposomal drug delivery and augurs well for the future of this treatment paradigm.