For the first time, a medication regime has been found effective for some patients with meth addiction in a large, placebo-controlled trial.
It's welcome news for those working with the growing number of people struggling with meth addiction.
"It's progress and it's quite significant," says Dr. Nora Volkow, director of the National Institute on Drug Addiction, which funded the two-year clinical trial involving roughly 400 patients.
The study was published Wednesday in The New England Journal of Medicine.
Unlike opioid addiction, for which medication-assisted treatment is the standard of care, no medication has been approved by the Food and Drug Administration for use with meth.
In the trial, patients in clinics around the U.S. suffering from methamphetamine use disorder were treated for 12 weeks with a combination of medications — naltrexone and bupropion — or placebo. The treatment helped 13.4% of patients with their addiction, compared with 2.5% of the placebo group.
While a success rate of just over 11% may not sound like a home run, Volkow noted that medications used to treat brain disorders, including mental illness and addiction, often have similar response rates in patients. This medication therapy provides another tool for doctors to try with patients.
"As we understand the complexity of the human brain, it becomes very much of a magical thinking that one pill will solve the problem of addiction," she says.
The project's lead researcher, Dr. Madhukar Trivedi at the University of Texas Southwestern Medical Center, says the findings were strong enough to give new hope to people struggling with meth use disorder.
"Patients who are struggling with meth use disorder should definitely have a conversation with their treating physicians to consider whether this option is something they should try," Trivedi said in a statement.
Lara Ray, a psychologist who studies medical treatments for addiction at UCLA and was not involved with this research, says the study changes the treatment landscape for roughly 1.6 million Americans who are addicted to methamphetamines.
"So far we have come up empty," Ray says. "I believe this clinical trial is really a breakthrough in many ways, because there have been so many failed trials."
The treatment regime in the trial combined two medications that have been studied separately for treating methamphetamine addiction with limited success.
Patients received injections of extended-release naltrexone and oral doses of bupropion. Naltrexone, which is already used for treating opioid addiction, blocks opioid receptors in the brain and is proven to reduce cravings in some patients. Bupropion is often used to treat depression.
Researchers say it's not entirely clear why these drugs worked more effectively in tandem.
Volkow says one theory is that naltrexone reduced physiological cravings for meth, while buproprion's "antidepressant effects" eased the anxiety people experience when they stop using. Unless treated, that emotional distress can trigger a relapse.
Ray says the success rate of the naltrexone-buproprion combination may be improved as doctors refine the method and when supported with other treatments, including behavioral therapy.
This clinical trial was successful enough that the National Institute on Drug Addiction's Volkow says she expects to move forward toward securing FDA approval. Meanwhile, she predicts some clinicians helping people in recovery will begin using the treatment immediately.
"Doctors are going to be reading about it and may prescribe the medications off-label to their patients," Volkow says. The trial did not reveal significant side effects.
This new medical treatment strategy arrives at a time when meth addiction has come roaring back, fueled by cheap imports from Mexico.
"It's almost like methamphetamines are falling from the sky right now, with the amount that's coming through the border and on boats and planes," says Matthew Donahue with the U.S. Drug Enforcement Administration.
According to the DEA, seizures of meth on the Southwestern border with Mexico have more than doubled in the last two years, to more than 170,000 pounds. Donahue acknowledged that effort hasn't put a dent in the supply.
"We see it down in Alabama, Mississippi and the Kentucky area where it's really taken off," Donahue says. He added that lack of medical treatments for those addicted to meth has complicated efforts to curb demand for the drug.
The human cost has been catastrophic. Researchers say overdose deaths linked to meth increased fourfold over the last decade.
In a public health alert issued last month, the Centers for Disease Control and Prevention warned meth fatalities spiked again more than 30% during the pandemic.
Even users who don't overdose often experience damage to the heart and other tissues, and can see their lives spiral out of control.
Jessica Martinez began using the drug when she paid her way through college as a sex worker. "I was shooting up every day, sometimes two to three times a day," she says.
Martinez, who has been in recovery for two years, now works with a Washington, D.C.-based group called HIPS helping others with meth addiction. She says when she started her recovery, it was hard in part because there were no medical treatments to help with cravings and withdrawal.
"For heroin users, there's methadone, there's suboxone. I just wonder why we haven't researched [treatments for] this drug yet," she says.
Martinez says she's hopeful more of her clients will now be able to get medical treatment for their meth addiction, rather than wind up caught in the criminal justice system. "It's about evidence-based care, it's about empathy and it's about survivability," she says.