uniQure Reports Encouraging Early Clinical Case Data for AMT-260 AAV Gene Therapy in Refractory MTLE

LEXINGTON, Mass. and AMSTERDAM, May 29, 2025 – uniQure N.V. today announced encouraging early clinical case study data from the first participant in its Phase I/IIa GenTLE trial of investigational AAV gene therapy, AMT-260, for refractory Mesial Temporal Lobe Epilepsy (MTLE). The data were presented at the Epilepsy Therapies & Diagnostics Development Symposium.

The first participant, followed for five months post-dosing, reported a significant reduction in seizure frequency. Prior to treatment, the participant averaged seven seizures per month, including five in the 30 days before dosing. Since receiving AMT-260, only two seizures were reported over five months, with none in the last 60 days (as of April 17th data cutoff). No serious adverse events were reported for this AAV treatment.

“These early results are very encouraging and support our belief that AMT-260 has the potential to be a valuable treatment alternative for drug-resistant MTLE patients,” stated Walid Abi-Saab, M.D., uniQure’s chief medical officer. “The reduction in seizure frequency and tolerability offer a compelling early signal that warrants continued investigation of this AAV gene therapy.”

AMT-260 is a one-time, in vivo gene therapy designed to reduce or eliminate seizures by locally delivering two engineered microRNAs to suppress the GRIK2 gene and aberrant GluK2 expression, believed to trigger seizures in refractory MTLE. This innovative approach leverages an AAV vector for precise delivery.

The GenTLE study (NCT06063850) is an open-label trial in the U.S. evaluating AMT-260’s safety, tolerability, and efficacy. It comprises two six-patient dose cohorts, with active screening across 12 sites and more expected by year-end, furthering the development of this AAV-mediated therapy.

About Refractory Mesial Temporal Lobe Epilepsy (MTLE): MTLE is the most common form of focal epilepsy, affecting over 600,000 individuals in the U.S. A majority of cases are drug-resistant, creating a high unmet medical need. Gene therapies, including those utilizing AAV vectors, are increasingly explored as potential long-term solutions.