In the study, designed to examine Nocaine's cocaine-like properties, the scientists found that research animals worked harder to get doses of Nocaine than to receive a placebo (saline solution). However, the amount of effort expended for Nocaine was significantly lower than the effort expended to obtain doses of cocaine.
"Our study results imply that Nocaine is a weak reinforcer--meaning that it provides some of cocaine's effects, but at a much lower level," said William L. Woolverton, PhD, professor of psychiatry at the University of Mississippi Medical Center, where this portion of the research was conducted.
Drugs that are weak reinforcers are less likely to be abused than strong reinforcers such as heroin or cocaine and therefore are less likely to have abuse-related toxicity. Earlier studies suggest that Nocaine may act to reverse the neurologic effects associated with acute cocaine abstinence (withdrawal), and that it blocks cocaine's stimulant effect. Nocaine is structurally similar to the popular antidepressant Paxil, although it acts on different neurotransmitters.
"Our studies have shown that Nocaine would likely blunt the aversive effects associated with cocaine abstinence, enabling addicts to gradually and safely withdraw from the drug," said Alan P. Kozikowski, PhD, professor of neurology and director of Georgetown's Drug Discovery Program.
Pending the outcome of final toxicology studies, Nocaine is expected to begin Phase I clinical trials in early 2003. (Phase I trials involve a small group of normal human subjects and are used to assess a drug's safety.)
In addition to being illegal, cocaine use causes many medical complications, including vascular occlusions that cause disturbances in heart rhythm and heart attacks; chest pain and respiratory failure; strokes, seizure, and headaches; and abdominal pain and nausea, according to the National Institute on Drug Abuse, which funded this research. In 2001, an estimated 1.7 million Americans were cocaine users, according to the National Household Survey on Drug Abuse.
Nocaine is being jointly developed by Georgetown University and its corporate sponsor, Cambridge, Mass.-based Biostream Inc., in conjunction with the National Institute on Drug Abuse.
Georgetown University Medical Center's Drug Discovery Program provides students and postdoctoral fellows with hands-on research experience and education in the field of cutting-edge drug discovery methods aimed at creating new drugs in three distinct therapeutic areas: cardiovascular, neuroscience, and cancer.
Journal of Pharmacology and Experimental Therapeutics