Polymer Nanospheres (PNS™) Technology Platform: From Concept to Commercialization
Biodegradable, hydrophobic polymer microspheres and nanospheres have been effectively used in the oral delivery of dicumarol, insulin and DNA plasmids in rats. While highly promising, hydrophobic microspheres still present challenges regarding formulation of a clinically acceptable product. The microspheres use organic solvents in synthesis e.g. methylene chloride and ethyl acetate. These methods cause human safety concerns regarding the toxic effects of residual solvent in the final product. Large-scale production of polymeric microspheres utilizing these processing steps and large quantities of organic solvents is time-consuming, costly and inefficient. In addition, the exposure of the therapeutic agent to the organic solvent can negatively affect the integrity of the final product and result in residual organics that may adversely influence drug stability and impact patients’ health and increase regulatory requirement burdens. Aphios has overcome these limitations through the utilization of near-critical, critical, and supercritical fluids with or without polar co-solvents (hereinafter referred to as SuperFluids™ [SFS]). These SuperFluids™ replace the usage of toxic organic solvents. These fluids exhibit enhanced thermodynamic properties of solvation, penetration, selection and expansion. In Aphios’ SuperFluidsÔ polymer nanospheres [SFS-PNS] process, a biodegradable polymer is dissolved in SuperFluidsÔ and decompressed through a nozzle into an aqueous solution containing the target therapeutic. As a result of decompression and density change, polymer films precipitate out of the SFS solution and hydrophobic polymer nanospheres are formed in the aqueous buffer encapsulating the target therapeutic.