CCTS pilot funding supports personalized brain stimulation research for methamphetamine use disorder
LEXINGTON, Ky. (Aug. 20, 2026) — Methamphetamine use disorder is notoriously hard to treat. Use and overdoses of the addictive psychostimulant have greatly increased over the last two decades, making it the second leading drug class in U.S. overdose deaths. But unlike other substance use disorders, there is currently no FDA-approved medication to assist in treatment, leaving only behavioral interventions.
Gopalkumar Rakesh, M.D., hopes to bring another treatment option into the mix. An assistant professor of psychiatry with expertise in non-invasive brain stimulation, he recently completed a pilot study using transcranial magnetic stimulation (TMS), personalized via functional MRI scans, to treat methamphetamine use disorder. TMS has been FDA-approved for treating depression since 2008, and in 2020 it received approval for treating smoking cessation.
“In substance use disorder treatment, we don’t have precision medicine like in oncology, for example. So this study explores a way to make TMS really individualized, not in terms of dose but in terms of where we are focusing the treatment,” he said.
His pilot study, funded by the UK Center for Clinical and Translational Science and co-led by Elizabeth Arnold, Ph.D., focused on using TMS to treat methamphetamine use disorder in people living with HIV, a particularly high-need population.
“Approximately 15 percent of people living with HIV have methamphetamine use disorder, compared with less than one percent of the general population,” he said. “It has drastic consequences for them — poor adherence to HIV medications, increased viral loads, worsening neurocognitive status, increased cardiovascular burden, and increased risk of mortality.”
Participants in the study were recruited from the Bluegrass Care Clinic, where Rakesh has been working with patients since 2019. The trust established through these long-term relationships allowed him to have “very delicate conversations” about the nonconventional intervention of TMS, which uses safe magnetic fields to stimulate nerve cells in the brain.
“It’s really rewarding to be able to offer these patients an alternative treatment,” he said.
The trial used a treatment and placebo arm to evaluate reduction in cravings and neural changes resulting from a potent TMS paradigm called intermittent theta burst stimulation (iTBS). Participants, all of whom were in remission from methamphetamine use, underwent fMRI scans while being shown neutral images and images related to methamphetamine use. This innovative method allowed Rakesh and Arnold to pinpoint where brain activity related to drug use and craving was most intense so the TMS could be focused there.
“While the brain activity was roughly in the same areas across the participants, the peak areas of activity varied by a few millimeters, and in the brain that can make a big difference,” he said. “This is a very novel aspect of the study. We had to test the method multiple times, and the CCTS funding was instrumental in allowing us to do that.”
The pilot study was small, but participants who received the TMS reported reduction in cravings, which their fMRI scans reflected.
“With fMRI data in this study, we saw some impressive changes indicating that the TMS was indeed acting on the part of the brain it was supposed to act on, as well as causing changes in other areas of the brain,” he said.
Rakesh also collected qualitative data from the participants, all of whom not only wanted to receive further TMS treatments but also indicated willingness to volunteer for other investigational treatments.
“What came through is that people with methamphetamine use disorder are often desperate for treatments because the cravings are so bad even when they’re in remission, and they’re so apprehensive of returning to use that they avoid a lot of potential triggers. Even holding down a job becomes difficult, which leads to further socioeconomic stressors,” he said.
The data from the pilot study supported Rakesh successfully applied for a $733,000 grant from Kentucky’s Opioid Abatement Commission. This funding will support a study using two weeks of intense TMS combined with maintenance sessions to help treat people with opioid use disorder (OUD) and depression.
“People with OUD might be treated with suboxone or buprenorphine but they can still experience cravings, and 50 percent return to use within six months,” he explained.
Rakesh has also submitted proposals for National Institutes of Health funding to continue this research. Additionally, he is collaborating with the UK Markey Cancer Center to study the use of TMS in cancer survivors, who experience elevated rates of smoking, substance use and chronic pain.
This cutting-edge research for TMS in multiple special populations is made possible, he says, only with support from many units and people across UK’s uniquely multidisciplinary campus — the Bluegrass Care Clinic, CCTS, Markey Cancer Center, fMRI scanning facility, and mentoring from Elizabeth Arnold, Ph.D., director of research in the UK College of Medicine department of psychiatry, and William Stoops, Ph.D., chair of the department of behavioral sciences and associate director of the CCTS.
“The goal is to become a leading voice in this space and have full clinical trials for TMS in substance use disorders so we can move it towards Food and Drug Administration clearance — which is the only way this treatment can be covered by insurance,” Rakesh said.
Media Contact: Mallory Profeta, mallory.profeta@uky.edu
