Pharmacokinetic and Pharmacodynamic Evaluation of Cocaine Hydrolases for the Treatment of Cocaine Overdose and Cocaine Addiction Using Rodent Models

Overdose and addiction are two medical complications of cocaine abuse. To date, there is no FDA approved pharmacotherapy specific for cocaine abuse. Cocaine hydrolases (CocHs) have been extensively investigated for its potential in anti-cocaine therapy. Previous studies have demonstrated that CocHs efficiently hydrolyze cocaine to generate biologically inactive metabolites both in vivo and in vitro. However, it has not been studied whether there is gender difference in the therapy using CocHs. In addition, the effectiveness of CocHs is unknown for treating cocaine toxicity when alcohol is co-administered. The main purpose of this dissertation is to characterize and evaluate efficient CocHs for cocaine overdose and cocaine addiction treatment. In the first set of studies, the effectiveness of human serum albumin-fused CocH1 were studied in male and female rats. The pharmacokinetic profiles, as well as the pharmacodynamic effects of CocH1-HSA were compared in male and female rats. The obtained data clearly demonstrated that CocH1-HSA was equally effective in both genders. The second set of studies investigated the efficiency of Fc-fused CocH5 in reversing cocaine toxicity in rats receiving simultaneous administration of cocaine and alcohol. Results showed that CocH5-Fc rapidly hydrolyzed cocaine and cocaine’s toxic metabolites in rats, and demonstrated that CocH5-Fc was efficient in treating cocaine toxicity when alcohol was simultaneously administered. In later studies to investigate the effects of CocH5-Fc for the treatment of cocaine addiction, a mathematical model was developed and validated to predict the effects of CocH5-Fc on the disposition of cocaine in rat blood and brain. This model adequately described the effects of CocH5-Fc in accelerating the elimination of cocaine and its toxic metabolites in both rat blood and brain. In conclusion, the studies within the current dissertation demonstrate the clinical potential of CocHs for the treatment of both cocaine overdose and cocaine addiction