PharmaGap Reports Significant Progress in Development of Liposomal Formulations of Cancer Drug GAP-107B8
Product News May 05, 2011
PharmaGap Inc. reports significant progress in development and initial testing of a liposomal delivery formulation for PharmaGap's lead cancer drug GAP-107B8 for therapeutic use in humans.
The development work has identified methods for encapsulating GAP-107B8 with efficiencies on the order of 90 to 100 percent, yielding liposomes of the desired particulate size for clinical use in humans.
A physiologically compatible buffer has been identified, and practical methods for concentration and sterile filtration of the preferred liposomal formulations have been developed. The sterile filtration process represents the final process step (from a technical perspective) which would be required prior to vialing product for clinical trial use.
PharmaGap has received liposomal formulations including both empty liposomes to be used as experimental controls, and liposomes loaded with PharmaGap's GAP-107B8. Internal in vitro cell proliferation assays with the unloaded control liposomes have been completed across cancer cell lines (including several ovarian and bladder cancer cell lines) to ensure optimal dosing strategies for peptide loaded liposomes.
Results from in vitro cell proliferation studies with GAP-107B8 loaded liposomes from the first set of prototypes are expected around the end of May. Prototype designs have been advanced based on their expected utility for topical delivery by intravesical infusion to the bladder wall; topical delivery by intraperitoneal injection for ovarian cancer; and by intravenous injection for solid tumours.
Liposomes are microscopic carriers with an aqueous core surrounded by one or more outer lipid layers, and release their contents by interacting with the targeted cells through adsorption, endocytosis, lipid exchange, or fusion.
Liposomal delivery is a means to modify the pharmacokinetic and pharmacodynamic properties of drugs with the objective of increasing efficacy and mitigating any potential side effects of drugs by enabling the delivery and targeting of the drug to the target site.
Liposomal delivery systems are an accepted, proven, and commercially viable strategy for the formulation of pharmaceuticals for clinical use. These lipid-based delivery systems are employed to improve tumour targeting, modulate the pharmacokinetics of the active agent and enhance its stability following administration. Therapeutic activity may be improved by modulating drug exposure and accumulation (controlled release) in the region where the target cancer cells are located.