Novel Drug Delivery System

About

There is a clinical need for localized drug administration providing sustained and/or controlled release for the treatment of numerous conditions, including ischemia, chronic pain, diabetes, and cancer. Such localized delivery is needed to (i) minimize patient exposure to the drug to decrease systemic toxicity, (ii) improve therapeutic results by achieving effective concentrations of the drug in the desired site for sufficient periods of time, and (iii) minimize the overall amount of drug to be administered. To meet this need, different polymer formulations that can be injected directly into the required site without the need for surgical implantation and retrieval have been developed. However, many of these systems have issues related to manufacturing, poor release kinetics, drug incompatibility, local tissue irritation, etc., especially for drugs that are sensitive to heat and/or changes in the local pH, such as biologics, peptides and proteins. Researchers at Queen’s University have developed a novel, injectable, liquid polymer drug delivery system intended for the localized delivery of low molecular weight chemotherapeutics, cytokines, growth factors, and other drugs/biologics that are susceptible to degradation in acidic environments. Based on biocompatible poly(aliphatic carbonates), the degradation products of this drug delivery system do not result in a significant reduction of the local pH, thereby, avoiding the issues associated with aliphatic polyester-based drug delivery systems. This drug delivery system is a viscous liquid depot at body temperature (and below) but is easily injected through standard gauge needles. The degradation and release profiles can be tailored to meet specific applications and can range between a few days to several months. Further, the drug can be added through a simple mixing procedure and local tissue irritation issues associated with solid depot and microsphere drug delivery technologies are avoided.