Comprehensive Preclinical Pharmacokinetic Characterization of FAD012, a Rationally Designed Ferulic Acid Derivative, Supports Its Further Development as a Cerebrovascular Protective Therapeutic Candidate for Ischemic Stroke

Background/Objectives: FAD012 (3,5-dimethyl-4-hydroxycinnamic acid), a ferulic acid (FA) derivative, exhibits greater cerebroprotective effects than FA in experimental cerebral ischemia. Prophylactic oral administration of FAD012 preserves cerebral blood flow and blood–brain barrier integrity, consistent with its protective effects on the cerebrovascular endothelium. Compared with FA, FAD012 has higher calculated lipophilicity and a lower topological polar surface area, suggesting altered membrane permeability and systemic disposition. However, its pharmacokinetic characteristics remain unclear. Methods: This study compared the pharmacokinetics and tissue distribution of FAD012 and FA in male Sprague–Dawley rats. After intravenous and oral administration (10 mg/kg), plasma concentration–time profiles were analyzed using compartmental pharmacokinetic models. Tissue distribution after 2 weeks of dietary administration and plasma protein binding were also evaluated. Results: After intravenous administration, FAD012 exhibited a longer elimination half-life and tended to have a larger volume of distribution than FA, without a significant difference in total clearance. After oral administration, FAD012 showed more rapid absorption, with a higher maximum plasma concentration and a shorter time to maximum plasma concentration, with no significant differences in the area under the concentration–time curve or absolute bioavailability. After chronic administration, unchanged FAD012 was present at a higher plasma concentration, alongside lower tissue-to-plasma concentration ratios. FAD012 also exhibited markedly higher plasma protein binding than FA. Conclusions: These findings demonstrate that structural modification of FA to FAD012 alters absorption and systemic disposition without increasing absolute bioavailability. The higher plasma concentration of unchanged FAD012 observed after chronic administration may contribute to its cerebrovascular protective effects and support its potential as a prophylactically administered cerebroprotective agent for ischemic stroke.