Polymer “shells” create microdroplets of biopharmaceuticals, enabling viscous drugs to be injected subcutaneously
Antibodies and other biopharmaceuticals have emerged as a powerful new class of drugs for treating diseases that range from rheumatoid arthritis to breast cancer to macular degeneration. However, these large, protein-based molecules cannot be taken orally (the stomach would digest them) and are frequently given at high concentrations. Most are administered intravenously, but that approach is time-consuming, expensive, and requires patients to physically go to clinics staffed by medical professionals – all problems that limit the scope and ease of treatment. Concentrating these drugs to the smaller volume needed for subcutaneous delivery often increases the viscosity of the drug solution to a point where it can no longer pass through a syringe, making injection impossible.
Researchers at the Wyss Institute at Harvard University are developing a novel system that allows viscous drugs to be injected subcutaneously through a needle using microfluidic encapsulation. This approach creates microdroplets of the drug within tiny polymer shells, resulting in a viscosity only slightly above that of water. By controlling the chemistry and shape of the polymer shells, drug release dynamics can be tailored as desired for specific applications. Initial proof-of-concept has been obtained with various FDA-approved polymer materials using high-concentration immunoglobulin solutions as model substances. Reaction conditions maintain biological activity without use of additional excipients, and result in encapsulation efficiencies of near 100%. In a collaborative effort with a drug developer, the Institute team is conducting a proof-of-concept study to test the viscosity and activity of a biologic drug before and after microfluidic encapsulation.
This video demonstrates the encapsulation of microdroplets of viscous drugs. Credit: Wyss Institute at Harvard UniversityThis technology is available for licensing for drug delivery.