Cerebellar transcranial magnetic stimulation to treat drug-resistant epilepsy: A randomized, controlled, crossover clinical trial.

Objective: Epilepsy is one of the most prevalent brain diseases. Approximately one third of patients consistently experience drug-resistant epilepsy (DRE), a condition where seizures persist despite the use of antiseizure medications. Exploration of new therapies for DRE is urgently needed. In this single-center, randomized, sham-controlled, crossover clinical trial (NCT05042726), we aimed to investigate the effectiveness and safety of transcranial magnetic continuous theta burst stimulation (cTBS) targeting the cerebellum to treat DRE.

Methods: Patients with DRE for ≥2 years and a seizure frequency of ≥2 seizures per month were enrolled and randomized 1:1 to receive active stimulation followed by sham stimulation or vice versa. The bilateral cerebellum was targeted by navigated cTBS focusing on the cerebellar dentate nucleus, once daily on workdays for 2 weeks. The primary outcomes were the percentage of seizure reduction and 50% responder rate in the per-protocol population within 2 months after treatment.

Results: Forty-four patients were enrolled and randomized; 18 patients in the active stimulation-first group and 20 in the sham stimulation-first group were included in the final analysis. Active cTBS significantly reduced seizures compared to sham stimulation (difference in percentage of seizure reduction between treatments = 25%, 95% confidence interval [CI] = 5%-46%, p = .018). The 50% responder rate after active stimulation was significantly higher than that after sham stimulation (difference in 50% responder rate between treatments = 24%, 95% CI = 11%-40%, p = .029). Adverse events occasionally occurred during active stimulation (moderate headache in 5% of patients, tinnitus in 3% of patients, dizziness in 3% of patients) but resolved spontaneously within days after treatment completion.

Significance: This trial suggested that cTBS targeting the cerebellum was effective and well tolerated in the treatment of DRE. Further studies are warranted to confirm its effectiveness and mechanism.