Cocaine esterase is a natural enzyme that breaks down the drug, and some researchers are investigating how it might be used to treat cocaine addiction, All Headline News reported Jan. 4.

Researcher Friedbert Weiss of the Scripps Research Institute said that a study using lab rats addicted to cocaine showed that those given a mutated form of cocaine esterase self-administered the drug less frequently than untreated rats. The enzyme reduces the addictive properties of cocaine, Weiss said.

The study, led by researchers at the University of Michigan Medical School and the University of Kentucky College of Pharmacology, was published in the November 2009 issue of the Journal of Pharmacology and Experimental Therapeutics.