Combining two FDA-approved drugs may help stop some people's use of methamphetamine, a new study shows.

Why it matters: Currently there are no FDA-approved drug treatments available for people with a methamphetamine use disorder — an addiction that has risen during the pandemic.

Preliminary CDC data shows overdose deaths from methamphetamine and similar stimulants increased 35% during the pandemic "as more people become anxious and depressed," says Nora Volkow, director of the NIH's National Institute on Drug Abuse (NIDA).

What's new: In a phase III clinical trial of 403 people with moderate to severe methamphetamine addiction (using the drug an average of 27 times per month), researchers gave the non-placebo groups a combination of extended-release naltrexone, used to treat opioid and alcohol use disorders, and bupropion, which is an antidepressant and nicotine cessation aid.

• Published in the New England Journal of Medicine Wednesday, the study found that at weeks 5 and 6, 16.5% of those given the combination drug responded, compared to only 3.4% of those in the control group. At weeks 11 and 12, 11.4% of the treatment group responded, compared to 1.8% of the control group.
• "This combination is almost six times better than placebo," says Madhukar H. Trivedi, lead author and chief of the mood disorders division at UT Southwestern Medical Center.
• Participants who took the drug also tended to report fewer cravings and no significant adverse side effects, he says.
• "This significantly increased the likelihood of people being able to stop taking methamphetamine," Volkow tells Axios. The medications are "reducing the urge of taking methamphetamine, and subjectively that is described by patients in having a reduction in craving. More objectively, it's seen by the fact that our patients are not taking it."

Background: Methamphetamine is highly addictive, as it raises the levels of dopamine and takes over the reward pathways in the brain. Methamphetamine use disorder also causes structural and neurochemical changes in the brain that can lead to severe health consequences or death.

• Volkow says there are likely several actions this drug combination may take that helps it to be effective: their antidepressant properties and how they may block certain chemical receptors that promote addiction.

What's next: Right now, the FDA has approved the individual drugs, which can be taken in combination as "off-label." "I would not have any hestitation advising clinicians to use it," Trivedi says.

• But, that also means insurance will sometimes not cover it, so the researchers are meeting with the agency to determine what steps would need to be taken for official combination drug approval.
• "It could be lifesaving if they use it and it's effective," Trivedi adds.

Of note: The study consisted of mostly white men, which is one limitation. The trial was partly funded by NIDA and Trivedi says he consults for some drug companies.

SAMHSA’s National Helpline is a free, confidential, 24/7, 365-day-a-year treatment referral and information service for individuals and families facing mental and/or substance use disorders. Call 1-800-662-HELP.