Researchers think they have finally found a treatment that works on methamphetamine addiction, but say more research is needed

As methamphetamine causes more addiction and death, treatment specialists have despaired for medicine to fight it. Now researchers may have found one.

A study published The New England Journal of Medicine found that a combination of two relatively familiar medications "was safe and effective in treating adults with moderate or severe methamphetamine-use disorder," the National Institutes of Health said in a news release.

The medicines are the antidepressant bupropion, usually sold as Wellbutrin, and naltrexone, which is use treat alcohol and opioid-use disorder. "The findings suggest this combination therapy may be a promising addition to current approaches to treatment, such as cognitive behavioral therapy and contingency management interventions, for a very serious condition that remains difficult to treat and overcome," NIH said.

Dr. Nora Volkow

The research was conducted in the clinical-trials network of the National Institute on Drug Abuse. NIDA Director Nora Volkow said, “There is a growing crisis of overdose deaths involving methamphetamine and other stimulants. However, unlike for opioids, there are currently no approved medications for treating methamphetamine use disorder. This advance demonstrates that medical treatment for methamphetamine use disorder can help improve patient outcomes.”

The study was conducted from 2017 to 2019 at clinics in drug-treatment programs across the country among 403 adult volunteers ages 18 to 65 who had moderate to severe meth-use disorder and said they wanted to stop or reduce use of the drug.

They were given an injection of extended-release naltrexone every three weeks and daily extended-release tablets of bupropion (or placebos, if in the control group). "Investigators performed four urine drug screens at the end of each stage of the trial," the release said. "Participants were considered to have responded to treatment if at least three of four urine screens were negative."

Overall, participants who for the treatment "responded at a significantly higher rate" than the control group, the release said; "When screened during weeks five and six, 16.5% of those given the naltrexone/bupropion combination responded, compared to only 3.4% of those in the control group. Similarly, when screened in weeks 11 and 12, 11.4% of the treatment group responded, compared to 1.8% of the control group."

Researchers calculated that the treatment was about as effective as most medical treatments for mental-health disorders, measured by their estimate that nine people would need to receive it in order for it to benefit one person.

That doesn't sound like a good success rate, but the release said, "Participants in the treatment group were assessed to have fewer cravings than those in the control group and reported greater improvements in their lives as measured by a questionnaire. . . . Importantly, there were no significant adverse effects."

Dr. Madhukar Trivedi, right, of the University of
Texas Southwestern Medical Center, led the research.

Long-term meth use causes changes in the brain that “can contribute to severe health consequences beyond addiction itself,” said Dr. Madhukar H. Trivedi of the University of Texas Southwestern Medical Center in Dallas, the lead researcher. “The good news is that some of the structural and neurochemical brain changes are reversed in people who recover, underscoring the importance of identifying new and more effective treatment strategies.” 

Bupropion and naltrexone had been tried alone on meth users, with limited, inconsistent effect. "Now, in combination, these compounds seem to have an additive or synergistic effect," the release said. "While there are U.S. Food and Drug Administration-approved medications for other substance use disorders, no medications have yet received FDA approval for methamphetamine use disorder. The effectiveness of this medication combination is progress toward improving treatment of this addiction."

The treatment is not ready for FDA approval. The researchers said they need to see if responses are better with longer treatment or concurrent behavioral therapy, such as contingency management, "which uses motivational incentives and tangible rewards to help a person attain their treatment goals," the release said. That has proven to be "the most effective therapy for stimulant-use disorders but is not widely used, stemming in part from a policy limiting the monetary value of incentives allowable as part of treatment."

"Experts have become increasingly concerned about the recent spikes in deaths from stimulant drugs including meth and cocaine," The Hill reports. "More than 16,000 people died from meth-related overdoses in 2019, a tenfold increase from 2009. The increase in deaths is likely in part due to a more potent meth coming from Mexico and laced with fentanyl, a synthetic opioid 50 to 100 times more powerful than morphine. Experts have worried the pandemic has worsened the problem, with more people turning to meth, relapsing in treatment and overdosing."