SAN DIEGO, Nov. 13, 2017 -- While there are no FDA-approved medicines to treat methamphetamine (meth) use disorders, researchers are reporting early findings of a second-generation gene therapy in animal models for meth abuse. Results being presented today at the 2017 American Association of Pharmaceutical Scientists (AAPS) Annual Meeting and Exposition demonstrate that the therapy lasts for over eight months, reducing the amount of meth in the brain and meth-induced stimulant effects.
The study, "Novel Anti-METH AAV-scFvs are Capable of Binding and Sequestering Methamphetamine and the Active Metabolite Amphetamine in the Blood" focused on the development of a long-lasting gene therapy treatment, which makes the body generate antibodies against meth. These antibodies tightly bind to both meth and amphetamine, an active metabolite of meth, in the blood stream and prevent it from traveling to the brain.
Eric Peterson, Ph.D., and his team from the University of Arkansas for Medical Science redesigned the therapy to deliver DNA to cells via a viral capsid, which then triggers the development of a protein to counter meth. Results achieved significantly higher concentrations of protective antibodies in the bloodstream of mice (n=8). Meth and amphetamine concentrations were 33 percent lower in brain tissue at 30 and 60 minutes, increasing to 50 and 68 percent respectively after 120 minutes. In a separate behavioral-based study, the medication was effective at reducing or abolishing meth-induced hyperactive movement in the mice at moderate doses of meth.
Peterson noted, "Imagine an IV bag delivering a constant infusion of the antibody, that is what this therapy is doing, using the body's own machinery to translate DNA to RNA to protein and have that circulate throughout the body, providing continuous meth protection."
Researchers will continue to characterize this anti-meth gene therapy in three primary ways. First, testing how effective the therapy is at keeping methamphetamine in the blood and out of the brain at several doses. Second, determining to what extent the therapy can protect against methamphetamine 's behavioral effects. Third, assessing how well it protects the brain against meth-induced effects, such as inflammation and stability of the blood-brain barrier.
"Even though our research is in the early stages, this treatment could ideally be effective for months to years after a single injection," said the study's lead author Charles Hay, M.S. "One day we envision that this treatment, or similar treatments could be combined with behavioral therapies to help users to quit using meth."