iposome formulations can be broadly divided into cationic, anionic and neutral subtypes. Cellsome® liposomes made from neutral PEGylated lipids provide certain benefits. One of the most well-known Neutral PEGylated Lipids used if for the drug Doxil®. Liposomal doxorubicin (Doxil®) is a liposome formulation encapsulating the chemotherapeutic drug, doxorubicin, thereby decreasing its toxicity.

To improve liposome stability and enhance their circulation times in the blood, a sterically-stabilized, hydrophilic polymer, polyethylene glycol (PEG), has been shown to be the optimal choice for obtaining sterically-stabilized liposomes. Using a Neutral Liposome with PEG will protect the liposomes from circulating proteins, improving their plasma clearance and enhancing their therapeutic effects. Doxil® also contains polyethylene glycol (PEG)-lipid resulting in pegylation of the liposome surface, which enables it to have a prolonged circulation and a reduced volume of distribution, thereby improving tumor uptake through the enhanced permeability and retention effect (EPR) and extending effective tumor therapy.

The three products provided that are made from Neutral PEGylated Lipids provided here consist of either HSPC:Chol:DSPE-PEG(2000) (65:30:5 molar ratio), DSPC:Chol:DSPE-PEG(2000) (65:30:5 molar ratio), or DOPC:Chol:DOPE-PEG(2000) (65:30:5 molar ratio).