Stimuli-responsive Self-Assembled Polymer Nanoparticles for the Oral Delivery of Antibodies.

Currently, commercially available antibody therapies must be delivered via parenteral administration. Oral delivery of antibodies could increase patient compliance and improve quality of life, however there is currently no viable system for delivering antibodies orally. In this work, a self-assembled, pH-responsive nanoparticle delivery system was developed to load and deliver antibodies via the oral route. The nanoparticles were synthesized via nanoprecipitation using the pH-responsive copolymers based on poly(methacrylic acid-co-methyl methacrylate)-block-poly(ethylene glycol). The reversibly hydrophobic nature of this polymer allowed it to function as an antibody delivery system via self-assembly. Characteristics of the polymer, including monomer ratios and molecular weight, as well as parameters of the nanoprecipitation process were optimized using Design of Experiments to achieve nanoparticles with desired size, polydispersity, loading efficiency, and release characteristics. Ultimately, the synthesized and optimized nanoparticles exhibited a hydrodynamic size within a range that avoids premature clearance, a low polydispersity index, and high IgG loading efficiency. In in vitro antibody release studies at physiologically relevant pH values, the nanoparticles exhibit promising release profiles. The nanoparticles presented in this work show potential as oral delivery vehicles for therapeutic antibodies.