Comprehensive composition analysis of doxorubicin HCl liposomes

Liposomal formulations, such as Doxil and its generics, have advanced cancer therapy by offering improved efficacy and reduced toxicity. The current study investigates advanced analytical capabilities to comprehensively analyze the lipid composition in doxorubicin HCl liposomes including lipid degradation products. Identification and quantification of lipid and cholesterol impurities and degradation products were performed using UHPLC-QTOF-ESI/APCI methods with SimLipid analysis. The identified lipids were cross verified using available lipid standards and the Lipid Maps Structural Database (LMSD). These analyses revealed two phospholipid impurities, PC(17,0-18:0) and PC(18,0-20:0), along with thirteen lipid degradation and cholesterol oxidation products, including six free fatty acids, four lysophospholipids, and three cholesterol and cholesterol derivatives. These phospholipid impurities were present at less than 2.4 mol% of the total lipids, while the major phospholipid degradation products such as LPC, LPE, and FFA were below 3.2 mol%. Cholesterol derivatives were also present at less than 0.1 mol% of total cholesterol. The detailed liposome composition analysis herein provides insight for the industry, especially for generic drug manufacturers that would like to conduct reverse engineering on the brand product to assure formulation sameness. Advanced lipid profiling can be used to determine chemical and lipid compositions of liposomal formulations.