- NON-MTS & BILATERAL MTLE: First data reported from non-MTS and bilateral MTLE subjects demonstrate robust seizure reduction
- LOW DOSE COHORT: 89% median reduction in disabling seizures for unilateral subjects with MTS at the primary efficacy evaluation period of 7-12 months post administration (n=9)
- HIGH DOSE COHORT: 78% median reduction in disabling seizures for unilateral subjects with MTS at interim efficacy evaluation period of 4-6 months post administration (n=9)
- DURABILITY: Several subjects have now surpassed the two-year mark, maintaining substantial seizure reduction
- COGNITION: No significant impairments detected in either dose cohort, with significantly increased test scores for some subjects
- SAFETY: NRTX-1001 continues to be well-tolerated at both high and low doses in bilateral and unilateral MTLE subjects, with and without MTS. No serious adverse events have been attributed to the cell therapy
- PIVOTAL TRIAL: EPIC Phase 3 trial of NRTX-1001 in drug-resistant MTLE is planned to dose first subjects in 1H 2026
SAN FRANCISCO, Dec. 08, 2025 (GLOBE NEWSWIRE) -- Neurona Therapeutics, a clinical-stage biotherapeutics company focused on advancing regenerative cell therapies for disorders of the nervous system, today presented new clinical results from its ongoing Phase 1/2 trials evaluating NRTX-1001, a one-time, allogeneic inhibitory interneuron cell therapy for drug-resistant mesial temporal lobe epilepsy (MTLE). The data were presented at the Annual Meeting of the American Epilepsy Society (AES), taking place December 5-9, 2025, in Atlanta, Georgia.
The updates include the first announcement of results from subjects without mesial temporal sclerosis (MTS) and from those with bilateral MTLE, expanding the clinical efficacy dataset for NRTX-1001 across a broader MTLE population. Additionally, several treated subjects have now been followed for more than two years, providing the most mature assessment to date of the therapy’s durability, safety, and impact on seizure burden.
“We are delighted to share this expanded 2025 clinical dataset at AES, which now includes our first outcomes from non-MTS and bilateral MTLE participants,” said Cory R. Nicholas, Ph.D., Neurona’s Co-Founder and Chief Executive Officer. “Across the program, we continue to see durable seizure reduction from a single administration of the product in most subjects, including median decreases of nearly 90% in the unilateral MTS low-dose cohort at the 7–12-month primary efficacy window, and more than 90% reduction in a subset of participants followed beyond 12 months. Moreover, several individuals have now surpassed the two-year mark, maintaining substantial seizure reduction with a consistent safety profile to date. These results further reinforce the potential of NRTX-1001 to deliver long-lasting, clinically meaningful benefits across a broader spectrum of people living with drug-resistant focal epilepsy.”
“We are now following some of our earliest participants out past two years, and the durability of their seizure reduction remains remarkable,” said Eduardo Dunayevich, M.D., Neurona Therapeutic’s Chief Medical Officer. “This year’s dataset also offers encouraging evidence that NRTX-1001 may extend benefits beyond the classic unilateral MTS population. The improvements we’re seeing across these patient cohorts continue to support the promise of NRTX-1001 as a potential treatment option for people with diverse forms of difficult-to-treat focal epilepsy. We look forward to treating the first participants in the Phase 3 EPIC trial in the first half of 2026.”
Results (n=26, data cut as of October 2025):
Low-Dose Cohort 1: Unilateral MTLE with MTS
- Interim Efficacy Endpoint: Months 4-6 Post-Administration (n=9)
- 80% median reduction in disabling seizures
- 78% (7/9) responder rate with ≥50% reduction in disabling seizures
- Primary Efficacy Endpoint: Months 7-12 Post-Administration (n=9)
- 89% median reduction in disabling seizures
- 78% (7/9) responder rate with ≥50% reduction in disabling seizures
- Long-Term Durability: Months 13+ (n=7)
- 92% median reduction in disabling seizures
- 86% (6/7) responder rate with ≥50% reduction in disabling seizures
High-Dose Cohort 2: Unilateral MTLE with MTS
- Interim Efficacy Endpoint: Months 4-6 Post-Administration (n=9)
- 78% median reduction in disabling seizures
- 89% (8/9) responder rate with ≥50% reduction in disabling seizures
- Primary Efficacy Endpoint: Months 7-12 Post-Administration (n=5)*
- 58% median reduction in disabling seizures
- 80% (4/5) responder rate with ≥50% reduction in disabling seizures
*(Four subjects have not yet reached 12-months of follow-up.)
Low-Dose Cohort 3: Unilateral MTLE without MTS
- Early Efficacy: Months 1-6 Post-Administration (n=4)*
- 88% median reduction in disabling seizures
- 67% (2/3) responder rate with ≥50% reduction in disabling seizures
*(Two subjects completed 6-months; One subject completed 3-months; One subject has not yet reached 1-month.)
Low-Dose Bilateral Study: Bilateral MTLE with or without MTS
- Early Efficacy: Months 1-6 Post-Administration (n=4)*
- 93% median reduction in disabling seizures
- 75% (3/4) responder rate with ≥50% reduction in disabling seizures
*(Two subjects completed 6-months; One subject completed 2-months; One subject completed 1-month.)
Safety Across All Cohorts
- No serious adverse events attributed to NRTX-1001 or the administration procedure.
- Procedure-related adverse events were mild to moderate and temporary.
- Immunosuppression-related adverse events were mild to moderate in severity and resolved in 9 of 10 participants who completed the regimen per protocol; one participant continues to report mild fatigue, irritability, and dizziness.
- Serious adverse events that did occur were consistent with underlying disease or unrelated conditions (e.g., episodes of status epilepticus consistent with prior histories, acute kidney injury in the context of illness, events related to a car accident).
Cognition and Quality of Life
- No group trends for decline in cognitive performance across word retrieval, verbal memory, or visuospatial memory assessments.
- 75% (6/8) of subjects demonstrated significant improvements in quality of life in epilepsy (QOLIE) test scores at 18 months post-treatment.
Neurona Therapeutics’ multicenter, open-label Phase 1/2 clinical program is designed to evaluate the safety, tolerability, and preliminary efficacy of a single administration of NRTX-1001 for drug-resistant MTLE. The ongoing unilateral MTLE study includes adults with and without MTS and has now enrolled participants across low- and high-dose cohorts. A parallel Phase 1/2 trial is evaluating NRTX-1001 in adults with bilateral MTLE, following low-dose administration to each hippocampus. Participants in both studies are monitored for safety, seizure frequency, and neuropsychological function.
In addition to completing enrollment of the current Phase 1/2 cohorts, Neurona is preparing to initiate the Phase 3 EPIC Trial, a randomized, sham-controlled, double-blind study designed to further evaluate NRTX-1001 in adults with drug-resistant MTLE. The EPIC study will randomize participants 2:1 to NRTX-1001 or sham control, with a six-month blinded period followed by the option for all eligible participants to receive treatment after unblinding.
For more information about Neurona’s clinical trials, please contact NeuronaMedInfo@neuronatx.com.
About Neurona Therapeutics
Neurona is developing allogeneic, off-the-shelf, regenerative neural cell therapies with the potential to provide long-term targeted repair of the nervous system following a single administration. Neurona’s lead product candidate, NRTX-1001, comprising GABAergic interneurons, is currently being studied for safety and efficacy in two ongoing open-label, multicenter Phase 1/2 trials: NCT05135091 for drug-resistant unilateral mesial temporal lobe epilepsy (MTLE), and NCT06422923 for drug-resistant bilateral MTLE, with expansion to neocortical focal epilepsy and other indications planned in the future. The Phase 1/2 MTLE clinical trials are supported by grants from the California Institute for Regenerative Medicine (CIRM; CLIN2-13355 and CLIN2-17135). The FDA granted the Regenerative Medicine Advanced Therapy (RMAT) designation to NRTX-1001 in June 2024. The EMA granted the Priority Medicines (PRIME) designation to NRTX-1001 in October 2025. Consistent with Neurona’s discussion with regulatory authorities, the Phase 3 EPIC (EPIlepsy Cell Therapy) trial is planned to dose first subjects in 1H 2026. For more information about Neurona, visit: www.neuronatherapeutics.com.
Investor Contact:
Laurence Watts
New Street Investor Relations
laurence@newstreetir.com
