A-PVP

Human pharmacokinetic evidence remains limited. In a naturalistic observational study of eight healthy volunteers who self-administered a single 10 mg or 20 mg intranasal dose, mean oral-fluid peak concentration occurred at 60 minutes after 10 mg and 47 minutes after 20 mg. Parent α-PVP and metabolites were recovered mainly in urine collected 2–5 hours after administration. The most abundant identified urinary product was an N-butanoic-acid metabolite formed by oxidative opening of the pyrrolidine ring, including a glucuronide; β-hydroxy-α-PVP was a minor metabolite. Because the study measured oral fluid and urine rather than serial plasma, it does not establish a human plasma half-life or absolute intranasal bioavailability. In non-vaccinated male rats given 0.56–3 mg/kg subcutaneously, serum kinetics were approximately linear and the terminal half-life ranged from 1.82 to 2.54 hours. Apparent distribution volumes of 14.1–17.9 L/kg and measured brain, heart, and kidney concentrations indicated extensive tissue distribution in this animal model. These subcutaneous rat values must not be presented as human or route-independent kinetics; absolute bioavailability was not measured because the study had no intravenous reference dose.