Autoinjectors are commonly employed by the United States and other countries to deliver emergency therapeutics to counteract the effects of various chemical agent threats, including nerve agents. Autoinjector combination products (autoinjector and drug product) used by the military can have drawbacks, including insufficient thermal stability of drug products, limited aqueous solution concentration of active pharmaceutical ingredients (APIs), and complicated and expensive designs for delivering multiple drugs simultaneously. We have developed a novel Enhanced Formulation (EF) technology that solves these problems, using nanoparticle suspensions in biocompatible cottonseed oil (CSO) instead of aqueous solutions of API. The hydrophobic CSO prevents hydrolytic degradation by limiting exposure to water, and the noninteraction of co-suspended particles simplifies multi-drug cocktail therapies. The high API loading (10% or more) gives the formulations non-Newtonian rheological behavior, with high zero-shear viscosity to resist sedimentation, and shear thinning to allow injection with standard autoinjectors and needles.

Keywords: Organophosphate; MMB4; nanoparticle; milling; intramuscular injection; formulation; particle size; suspension; non-Newtonian; shear thinning; enhanced formulation; nerve agent antidote; nerve agent intoxication; medical countermeasure; cottonseed oil