London and San Sebastián, Spain – September 12, 2026 -- EpilepsyGTx has partnered with AAV-focused CDMO Viralgen to manufacture EPY201, an investigational gene therapy targeting focal refractory epilepsy (FRE), a condition affecting an estimated 10 million patients worldwide, including 2 million across the US, UK and EU.
Viralgen's Aava platform will scale EPY201 production ahead of first-in-human trials
Under the agreement, Viralgen will deploy its proprietary Aava manufacturing platform to produce EPY201 at scale. The platform has already supported production of 1,500 AAV batches and is designed to handle all AAV serotypes with high-yield output. Viralgen's San Sebastián facility operates three cGMP suites, each with 2,000-liter capacity, certified by AEMPS/EMA, alongside plasmid production, process optimization, fill-finish and internal QC testing.
EPY201 targets seizure foci directly, aiming for single-treatment seizure freedom
EPY201, also known as AAV9-CAMK2A-EKC, uses an AAV9 capsid, a CAMK2A promoter, and an engineered version of the Kv1.1 potassium channel. Administered via intraparenchymal delivery directly to the brain region responsible for seizures, the therapy is designed to reduce neuronal hyperexcitability without resection or ablation of brain tissue. EpilepsyGTx plans to initiate first-in-human trials for EPY201 in the first half of 2027.
Refractory epilepsy persists despite trials of at least two antiepileptic drugs
Focal epilepsy is classified as refractory, or pharmacoresistant, when seizures continue after patients have tried at least two well-tolerated, appropriately selected antiepileptic medications. EpilepsyGTx, founded in 2021 based on research from the University College London Institute of Neurology, has generated preclinical evidence of anticonvulsant activity and tolerability across multiple seizure-focus locations.
Nicolas Koebel, CEO of EpilepsyGTx, said Viralgen's manufacturing expertise and regulatory track record will be critical as the company advances EPY201 toward clinical development. Viralgen was established in 2017 as a subsidiary of AskBio Inc. within the Bayer AG group and uses its proprietary Pro10 suspension cell line alongside the Aava platform for scalable AAV production.