Encoded Therapeutics Raises $275M Series F to Push ETX101 Gene Therapy Through Pivotal Dravet Syndrome Development
核心洞察
Encoded Therapeutics (搜索) closed a $275 million Series F financing co-led by GV (搜索) and an undisclosed healthcare fund, with participation from ARCH Venture Partners, SoftBank Vision Fund 2 and others.
Proceeds will fund a pivotal trial of ETX101 in infants and young children with SCN1A (搜索)-positive Dravet syndrome (搜索) plus an expansion study up to age 18.
Interim Phase 1/2 POLARIS data presented at the European Epilepsy Congress showed up to 79% reductions in monthly seizures at the third dose level after one year.
Encoded Therapeutics (搜索) Inc. has closed a $275 million financing that will carry its lead precision genetic medicine, ETX101, into pivotal development for SCN1A (搜索)-positive Dravet syndrome (搜索), the South San Francisco-based clinical-stage company announced. The round was co-led by GV (搜索) and another healthcare fund, with participation from ARCH Venture Partners, Braidwell LP, Farallon Capital Management, Illumina Ventures, Invus, Janus Henderson Investors, Matrix Capital Management, Nolan Capital, RTW Investments, SoftBank Vision Fund 2, and Venrock.
The raise follows interim Phase 1/2 POLARIS results presented at the European Epilepsy Congress, which the company said demonstrated substantial and sustained seizure frequency reductions alongside encouraging developmental gains. According to the company, a single administration of ETX101 at the third dose level reduced monthly seizures by up to 79% in patients who completed a full year of follow-up, with reductions described as measured against historical controls.
"The interim Phase 1/2 POLARIS data we recently shared at the European Epilepsy Congress demonstrate substantial and sustained seizure frequency reductions alongside encouraging developmental gains. This progress strengthens our conviction in ETX101 and the potential of our approach to meaningfully alter the course of Dravet syndrome (搜索)," said Kartik Ramamoorthi, Ph.D., Chief Executive Officer of Encoded. "With pivotal development underway, this financing gives us the resources to advance ETX101 toward registration while continuing to build the capabilities and pipeline that will define Encoded's next stage."
Pivotal Program and Expansion Cohort
Proceeds will support the pivotal study of ETX101 in infants and young children with SCN1A (搜索)+ Dravet syndrome (搜索), as well as an expansion study in children and adolescents up to 18 years of age. Encoded has not disclosed a timeline for completing the pivotal trial or for a potential Biologics License Application submission.
ETX101 is a one-time AAV9-based gene therapy designed to selectively increase expression of a healthy copy of SCN1A (搜索) in inhibitory neurons, targeting the underlying genetic cause of the disease rather than managing symptoms alone. More than 90% of Dravet syndrome (搜索) cases stem from loss-of-function mutations in the SCN1A gene, according to the source materials. The condition is a severe developmental and epileptic encephalopathy that begins in infancy and causes prolonged seizures that respond poorly to current anticonvulsant drugs, along with behavioral and developmental delays.
Dravet syndrome (搜索) affects an estimated one in every 16,000 live births and accounts for roughly 0.17% of all epilepsy cases, according to the National Organization for Rare Disorders. There are no approved disease-modifying treatments for the condition.
Manufacturing Scale-Up and Pipeline
Beyond the Dravet program, the financing will fund commercial scale-up of Encoded's internal GMP manufacturing capabilities, a move the company frames as giving it greater control over production as it approaches potential commercialization. The capital also supports pipeline advancement, including ETX301, an AAV9-based vectorized microRNA gene therapy for post-amputation neuroma pain (搜索), toward a 2027 Investigational New Drug submission.
Encoded describes its vector engineering platform as enabling highly targeted, cell-type-selective control of gene expression in the brain and peripheral nervous system, allowing precise modulation of disease-relevant genes. The company's stated focus spans one-time treatments for severe monogenic and common neurological disorders, supported by an end-to-end engine covering discovery, development, and in-house GMP manufacturing.
Investor Perspective
GV (搜索) general partner Brendan Bulik-Sullivan, Ph.D., said the emerging clinical profile of ETX101 is "increasingly compelling, with durable seizure control and promising neurodevelopmental signals, reinforcing its potential as a transformative therapy. We are pleased to co-lead this financing and support Encoded as it advances ETX101 through pivotal development."
David Schenkein, M.D., General Partner and Co-Lead of Life Sciences at GV (搜索), added that progress with ETX101 provides validation of Encoded's differentiated approach to genetic medicine and the broader potential of its platform. "Encoded is well positioned to build a significant portfolio of medicines across neurological diseases, where more precise and durable biological intervention could meaningfully improve outcomes," he said.
Competitive Landscape in Dravet Syndrome
Encoded is not alone in pursuing the underlying genetic cause of Dravet syndrome (搜索). Stoke Therapeutics is developing zorevunersen, an antisense oligonucleotide that instructs cells to produce a healthy copy of the SCN1A (搜索) gene. In 2025, Biogen paid $165 million upfront for U.S. rights to the asset as part of a deal worth up to $550 million that also covered territories outside Canada, Mexico, and the United States. Stoke and Biogen expect a readout from the Phase III EMPEROR study in the middle of next year.
Encoded, by contrast, is still preparing to begin its pivotal trial, placing the two programs at different stages of clinical development. Whichever therapy reaches patients first could establish a meaningful commercial advantage in a rare disease market with no approved disease-modifying treatments. The company's path to this point included a difficult trade-off: in February 2025, Encoded laid off 29% of its workforce to fund the Phase 1/2 trial.
The $275 million round ranks among the largest private financings in the gene therapy sector this year, signaling continued investor appetite for neurology-focused platforms that pair clinical-stage assets with internal manufacturing capabilities.
