uniQure has reported encouraging early clinical results from its experimental gene therapy AMT-260, offering new hope for patients living with refractory mesial temporal lobe epilepsy (MTLE), one of the most difficult forms of epilepsy to treat.
The company presented initial six-month follow-up data from the first cohort of patients enrolled in its ongoing Phase I/IIa clinical trial at the Epilepsy Foundation Pipeline Conference held in Leesburg, Virginia. The findings represent an important early milestone for the investigational therapy, which is designed as a one-time treatment intended to reduce or potentially eliminate seizures.
According to the data, three of the six patients treated in the study’s first low-dose cohort experienced substantial reductions in disabling seizures during months four through six after treatment. The reductions ranged from 79% to 100% compared with baseline seizure levels. Notably, one patient reported complete elimination of disabling seizures during the assessment period.
The remaining three participants showed more variable outcomes. Changes in disabling seizure frequency ranged from a 33% reduction to a 36% increase compared with baseline. While the results demonstrate differing responses among patients, the company believes the data provide early evidence that the therapy is biologically active.
Equally important, the treatment has so far demonstrated a favorable safety profile. As of the latest data cutoff in late May 2026, no serious adverse events related to either AMT-260 or the surgical administration procedure had been reported. All observed side effects were classified as mild or moderate, with headaches being the most commonly reported adverse event. Researchers also noted that no immunosuppressive therapy was required following treatment.
Walid Abi-Saab, Chief Medical Officer of uniQure, said the findings are encouraging despite the small patient population and relatively short follow-up period.
He noted that while responses have varied between patients, the observed seizure reductions and favorable tolerability profile support continued clinical evaluation of the therapy. Abi-Saab emphasized that additional follow-up and larger patient numbers will be needed to better understand the treatment’s long-term potential.
AMT-260 is being developed specifically for patients with refractory mesial temporal lobe epilepsy, a condition in which seizures remain uncontrolled despite treatment with available anti-seizure medications. The disorder affects a significant portion of epilepsy patients and can severely impact quality of life.
Unlike traditional epilepsy treatments that focus on symptom management, AMT-260 aims to address an underlying biological cause of seizures. The gene therapy delivers two engineered microRNAs directly into the brain to suppress the GRIK2 gene and reduce production of the GluK2 receptor subunit, which researchers believe contributes to seizure activity in refractory MTLE.
The ongoing GenTLE study is being conducted at multiple centers across the United States. The trial is evaluating two dosing levels, with up to six patients enrolled in each cohort. Participants receive a one-time intracerebral infusion of the therapy and are monitored during a 12-month evaluation period followed by four years of long-term follow-up.
Enrollment is currently underway in the second, higher-dose cohort, which is expected to include six patients. The company anticipates completing enrollment by mid-2026 and plans to provide updated clinical results during the first half of 2027.
The development of AMT-260 reflects growing interest in gene therapies for neurological disorders. If future studies confirm the early findings, the treatment could offer a new therapeutic option for thousands of patients with drug-resistant epilepsy who currently have limited alternatives beyond invasive surgery or neurostimulation devices.
Although still in the early stages of development, the initial results suggest that AMT-260 may have the potential to become a transformative treatment for patients struggling with refractory mesial temporal lobe epilepsy.