uniQure N.V. has reported encouraging early results from the first patient treated with its investigational gene therapy AMT-260 for drug-resistant mesial temporal lobe epilepsy (MTLE), showing a 92% reduction in seizure frequency with no serious adverse events during five months of follow-up. The data were presented at the Epilepsy Therapies & Diagnostics Development Symposium in Leesburg, Virginia.
Dramatic Seizure Reduction Observed
The first participant in the GenTLE clinical trial experienced a significant improvement in seizure control following a single administration of AMT-260. Prior to treatment, the patient suffered an average of seven seizures per month, including five seizures in the 30-day period immediately before dosing. After receiving the gene therapy, the participant reported only two seizures during the entire five-month follow-up period, with no seizures occurring during the final 60 days as of the April 17th cutoff date.
"These early results from the first trial participant are very encouraging and support our belief that AMT-260 has the potential to be a valuable treatment alternative for people living with drug-resistant mesial temporal lobe epilepsy," stated Walid Abi-Saab, M.D., chief medical officer of uniQure.
Novel Gene Therapy Mechanism
AMT-260 represents a one-time administered, in vivo gene therapy designed to reduce or eliminate seizures in patients with drug-resistant MTLE. The therapy works by locally delivering two engineered microRNAs that suppress the GRIK2 gene and the aberrant expression of GluK2, a subunit of a kainate glutamate receptor believed to trigger seizures in people with refractory MTLE.
This targeted approach addresses the underlying molecular mechanisms of seizure generation, potentially offering a more definitive treatment option compared to traditional anti-seizure medications that many MTLE patients cannot tolerate or respond to adequately.
Addressing Significant Unmet Medical Need
Temporal lobe epilepsy affects more than 600,000 individuals in the United States and represents the most common form of focal epilepsy. Approximately 80% of all temporal lobe epilepsy cases are mesial, involving the medial structures of the brain. The majority of MTLE cases prove refractory to anti-seizure medications, severely limiting treatment options for patients.
"There remains a high unmet need for safer, more effective treatment options for people with drug-resistant MTLE and we're eager to continue evaluating AMT-260 in additional trial participants," Abi-Saab noted.
Clinical Trial Design and Progress
The GenTLE study is a Phase I/IIa multi-center, open-label trial being conducted across the United States to evaluate the safety, tolerability, and exploratory signs of efficacy of AMT-260 in individuals with refractory MTLE. The study comprises two dose cohorts of six patients each and is actively screening additional patients throughout 12 sites, with additional sites expected to be activated by the end of 2025.
While Abi-Saab emphasized that additional follow-up on the first trial participant and data from additional participants are needed, the reduction in seizure frequency and tolerability observed in this initial case "offer a compelling early signal of the potential impact of AMT-260 that warrants continued investigation."
Company Background
uniQure has established itself as a leader in gene therapy development, with previous approvals for gene therapy treatments including a therapy for hemophilia B. The company is advancing a pipeline of proprietary gene therapies for various severe diseases, including Huntington's disease, ALS, and Fabry disease, in addition to refractory temporal lobe epilepsy.
