Stroke accounts for about 1 of every 14 deaths in the United States making it the third leading cause of death. It is also the number one cause of disability, with more than 3 million people currently living with permanent physical and mental impairment from brain damage caused by stroke. BioPhyZica has developed a treatment, known as HES-Z + VitC, for treating capillary leak, edema, and reperfusion injury caused by ischemic stroke. HES-Z + VitC consists of a solution of hydroxyethyl starch (HES) molecules in a specific molecular weight range in combination with an antioxidant additive, ascorbic acid, hereafter referred to as HES-Z + VitC. The hydroxyethyl starch component provides a biophysical action of sealing at capillary endothelial gaps (pores) that develop after stroke, while the antioxidant enhances the overall efficacy by reducing reperfusion injury. The goal of this Phase I STTR research is to demonstrate, in an animal model, that HES-Z + VitC can reduce the neurological deficit after ischemic stroke.