1. Observation Period: Primary objectives: To observe and characterize seizure frequency via study-specific electronic seizure diaries in adults with unilateral refractory MTLE.
2. condary: -To observe and characterize electroencephalogram (EEG) via 48-hour EEG recording. -To observe and characterize patient-reported outcomes (PROs). B) Evaluation Period Primary: To evaluate the safety and tolerability of AMT-260 in adults with unilateral refractory MTLE. Secondary: -To evaluate the biodistribution, first signs of efficacy, and pharmacokinetic properties of AMT-260. -To determine the recommended dose for upcoming studies. Primary safety endpoint: Occurrence of AEs during the Evaluation Period, including seriousness, severity, and causal relationship to AMT-260. Efficacy endpoints: -Change from Observation Period to each 30-day segment of the Evaluation Period in seizure frequency, based on Observation Period seizure diary data. -Clinical response at each 30-day segment of the Evaluation Period, defined as at least 50% reduction from Observation Period in seizure frequency during that segment, based on Observation Period seizure diary data. -Change from the 3-month Retrospective Period to each 30-day segment of the Evaluation Period in seizure frequency, based on retrospective data. -Logarithmically transformed seizure frequency during each 30-day segment of the Evaluation Period in seizure frequency. -Seizure freedom over each 30-day segment of the Evaluation Period. -Category of seizure response (greater than 25% worsening, less than or equal to 25% to greater than 0% worsening, 0 or greater to less than 25% improvement, at least 25 % to less than 50% improvement, at least 50% to less than 75% improvement, at least 75% to 100% improvement) at each 30-day segment of the Evaluation Period, based on Observation Period seizure diary data. -The proportion of participants with 1 or more clinically relevant change in PROs using the following instruments: QOLIE-31, PHQ-9, STAI, and PSQI assessed on TD14, TD28, TD132, TD252, and TD365. Secondary safety & biodistribution endpoints: -the proportion of participants with at least 1 clinically relevant change from the observation period end (OP End) in T2 and T2 fluid-attenuated inversion recovery (FLAIR) weighted brain MRI images assessed on TD7, TD14, TD28, TD72, TD132, TD252, and TD365. -The proportion of participants with at least 1 clinically relevant change from the Observation Period (OP End) in routine laboratory parameters assessed on TD2, TD4, TD7, TD14, TD28, TD132, TD252, and TD365 (hematology, biochemistry, coagulation, urinalysis) and plasma levels of concomitant medication. -Laboratory tests (blood serum) to assess the immune response to AMT-260 (anti-AAV9 neutralizing antibodies [NAbs]) on TD -1/TD1 Pre-IMP, TD2, TD7, TD14, TD28, TD132, TD252, and TD365. -Laboratory tests (blood serum, urine, saliva) to assess vector and miRNA biodistribution and shedding (AAV9, mature miRNA) on TD -1/TD1 Pre-IMP, TD2, TD7, TD14, TD28, TD132, TD252, and TD365, analyzed as needed. -Laboratory tests (cerebrospinal fluid [CSF]) to assess the immune response to AMT-260 (anti-AAV9 NAbs) on TD -1/TD1 Pre-IMP, TD14, TD132, and TD365. -Laboratory tests (CSF) to assess vector and miRNA biodistribution and shedding (AAV9 vector deoxyribonucleic acid (DNA) genome copies, copies of mature miRNA) on TD -1/TD1 Pre-IMP, TD14, TD132, and TD365. -Laboratory tests (CSF) to assess neurodegeneration (neurofilament light chains [NfLs]) on TD -1/TD1 Pre-IMP, TD14, TD132, and TD365. -Clinically relevant changes in vital signs assessed on TD2, TD7, TD14, TD28, TD42, TD132, TD252, and TD365. -Clinically relevant changes in physical examinations and neurological examinations assessed on TD14, TD28, TD42, TD132, TD252, and TD365. -Clinically relevant changes from the Observation Period (OP End) in 12-lead electrocardiogram (ECG) assessed on TD14, TD28, TD132, TD252

You may be eligible for this study if you meet the following criteria:

• Conditions: Medical Research
• Age: - 99 Years
• Gender: All