By Steps to Recovery on November 9, 2012
A recent study by scientists working for The Scripps Research Institute (TSRI) is showing what some consider promising results in developing a vaccine for Methamphetamine. Tests run on vaccinated rats who were receiving meth show that the animals were largely protected from typical symptoms of meth intoxication. Basically, this vaccine is similar to a vaccine against an illness. It is designed to attach to the drug molecules and prevent them from entering the brain. If the vaccine has the same effect on humans, this could be considered the first ever specific treatment for methamphetamine addiction.
“This is an early-stage study, but its results are comparable to those for other drug vaccines that have then gone to clinical trials,” said Michael A. Taffe, an associate professor in TSRI’s addiction science group, known as the Committee on the Neurobiology of Addictive Disorders. Taffe is the senior author of the study, which is currently in press with the journal Biological Psychiatry.
Methamphetamine has become one of the most common and destructive recreational drugs in the country. In the United States, government data estimate that there are currently more than 430,000 users, with more than 41,000 new users this year. The drug can cause psychosis, and its stimulatory effects are considered 50 times stronger than cocaine, keeping people awake for days, and treatment for the drug is a very difficult process.
Recently, scientists have taken the a new approach to combat addiction by working to develop vaccines against addictive drugs. These vaccines evoke antibody responses against drug molecules, just as traditional vaccines evoke antibody responses against viruses or bacteria. Anti-drug antibodies are meant to grab hold of drug molecules and keep them from getting into the brain — preventing the drug from giving the user a high and removing the incentive for taking the drug.
The first several meth vaccines that were presented for testing by Kim Janda, the Ely R. Callaway, Jr. Professor of Chemistry and member of the Skaggs Institute for Chemical Biology at TSRI, didn’t look promising because “The simple structure and long half-life of this drug make it a particularly difficult vaccine target,” according to Janda. However, in a new study scientists investigated the most successful of the vaccines using a different experimental setup and found that it prevented a rise in body temperature and burst of wheel-running hyperactivity that otherwise occur after meth exposure. Underlying these promising effects on behavioral measures was a robust antibody response, which in vaccinated rats kept more of the drug in the bloodstream and out of the nervous system, compared to control rats. They hope to follow up with more animal testing and perhaps clinical testing in humans one day.
Taffe said while the results are promising, the research is still in its infancy. The vaccine is not as long lasting as the researchers would like – the effects last weeks, not years – and they still have other questions that need to be answered.
Such as, how to make the vaccination affordable, and the golden question….Will rats stop craving the drug if on the vaccine?
“It’s looking promising,” said Taffe, “but we’re still pretty early on in the process.”