Microhydrogel Depot for Sustained Delivery of Prophylactic Bioscavenger

Countering the threat of intoxication by organophosphorus nerve agents is an important mission for homeland security. Currently, the most promising strategy is to bioscavenge the agents using injectable plasma-derived butyrylcholinesterase (BuChE) that has low substrate specificity and may offer a broad spectrum protection against OP agents. Human plasma-derived BuChE at 400mg IV dose is prophylactically effective achieving good protection for 10 days. However the current unmet need is a single non-IV administration capability to deliver BuChE and sustain the plasma concentration at 80-200 g/mL for up to 60 days. Luna is developing an intramuscularly injectable physiological depot engineered to release BuChE at specific rates. The Phase I results demonstrated the feasibility of the technology by both experimental data and PK modeling. The microhydrogel depot continuously released BuChE for periods up to 60 days and PK simulation data showed that the depot formulations were able to provide BuChE plasma concentrations above the protective threshold level (2xLD50) for>50 days. In the Phase II period, the depot technology will be optimized and extensively assessed in proper animal models for pharmacokinetics, efficacy and safety performance. Luna will also work with JPEO-CBD to define a product development strategy and a clinical regulatory pathway.