BIOTEK proposes to develop a new method for incorporating drugs into an implantable system suitable for prolonged depot delivery. The technique is simple, mild, and efficient, and its successful development and commercialization could provide the first route to a generic long-term parenteral delivery system for therapeutic proteins and peptides. The process is made possible by the availability of very high molecular weight poly-L-actide, a polymer which, even as a thin walled capsule, remains strong enough to permit early surgical removal, yet which resorbs with no need for surgery once delivery is complete. The process gives high yields and does not expose the drug to solvents or harsh conditions, making it particularly appropriate for unstable or costly drugs such as proteins. In Phase I BIOTEK will prepare and characterize capsules with and without porosity-enhancing agents, measure tensile and burst strength, load capsules with various enzymatic proteins, follow total delivery in vitro, confirm the activity of the released proteins, investigate the ease of implantation and removal, and investigate any tissue irritation response in rabbits. Phase I is intended to confirm the broad utility of the method and to provide evidence for continuous delivery lasting more than 3 months. On the basis of that information a medicinal peptide or protein will be selected for initial product development during Phase II, which will include GMP manufacture, quality assessment, stability testing, IND submission, and initial human testing.
An economical, safe and effective way to formulate proteins and peptides into biodegradable implants capable of prolonged delivery would eliminate the need for frequent injection for such drugs, and a similar method should find application for chronic delivery of other potent compounds such as steroids and prostaglandins.
