Where Encoded's $275 million Series F goes, and the data behind it A tree diagram of Encoded Therapeutics' $275 million Series F financing, whose close was announced on September 9, 2026, co-led by GV and an unnamed healthcare fund. The round splits into three uses: ETX101's pivotal ENDEAVOR Part 2 study in children aged 6 months to 4 years plus an expansion study up to age 18; commercial scale-up of Encoded's in-house GMP manufacturing; and pipeline work taking ETX301 toward a 2027 IND. The split between the three uses is not disclosed. A band below summarises the latest interim POLARIS Phase 1/2 data, with an August 3, 2026 cutoff: a median reduction in monthly countable seizure frequency at month 12 of about 79% at dose level 3 (3 participants) and about 89% at dose level 4 (5 participants), and no treatment- or procedure-related serious adverse events with up to 117 weeks of follow-up. The pivotal study is ongoing. Where Encoded’s $275M Goes Series F close announced September 9, 2026, co-led by GV and an unnamed healthcare fund. The split between the three uses is not disclosed. $275M Series F ENCODED THERAPEUTICS · PRIVATE ETX101 pivotal + expansion PIVOTAL · AGES 6 MO–4 YR · ONGOING EXPANSION · UP TO AGE 18 In-house GMP manufacturing COMMERCIAL SCALE-UP INTERNAL GMP CAPABILITIES Pipeline ETX301 · IND TARGET 2027 POST-AMPUTATION NEUROMA PAIN The latest data: POLARIS Phase 1/2 interim results, data cutoff August 3, 2026 Month 12, median reduction in monthly countable seizure frequency: ~79% at dose level 3 (n=3), ~89% at dose level 4 (n=5) No treatment- or procedure-related serious adverse events across four dose levels, up to 117 weeks of follow-up Open-label dose escalation, reported by the sponsor. The pivotal ENDEAVOR Part 2 study is ongoing. All figures as reported by Encoded Therapeutics, press releases of September 8 and September 9, 2026.

One raise, three uses: the pivotal program, in-house manufacturing, and pipeline work including ETX301's path to an IND

Encoded raised $275 million to take its Dravet gene therapy through a pivotal study.
The same round pays to scale up its own commercial manufacturing while that study is still running.

Encoded Therapeutics announced the close of a $275 million Series F on September 9. The money will support pivotal and expansion studies of ETX101, an investigational AAV9-based gene regulation therapy for SCN1A+ Dravet syndrome designed as a one-time treatment. It will also support commercial scale-up of in-house GMP manufacturing and pipeline advancement, including ETX301 toward a 2027 IND submission.

What was announced

Encoded Therapeutics is a privately held biotech in South San Francisco. On September 9 it announced the close of a $275 million Series F, co-led by GV and a second healthcare fund the company did not name.

Eleven more investors took part, among them ARCH Venture Partners, Farallon Capital Management, RTW Investments, SoftBank Vision Fund 2 and Venrock. The full list is in the FAQ below.

For a therapy whose pivotal study is still running, the notable part of this round is that it buys more than trials.

Where the money goes, per Encoded

CEO Kartik Ramamoorthi said the financing gives Encoded "the resources to advance ETX101 toward registration" with pivotal development already underway.

The data Encoded released the day before the round

The raise was announced a day after Encoded's September 8 release on updated Phase 1/2 POLARIS data, presented at the 16th European Epilepsy Congress in Athens. The analysis uses an August 3, 2026 data cutoff.

From week 5 through week 52, or each participant's latest visit, the median reduction in monthly countable seizure frequency was about 76% at dose level 3 (n=5). At dose level 4 (n=9) it was about 60%. Among participants who completed 52 weeks, the month-12 median was about 79% at dose level 3 (n=3) and 89% at dose level 4 (n=5).

At dose level 4, about 60% median seizure reduction across weeks 5 to 52 (n=9), and about 89% at month 12 (n=5).

These are interim Phase 1/2 results from small, open-label cohorts, and the figures are the sponsor's own. The month-12 numbers rest on eight participants in total; the reported week 5 to 52 figures cover 14, and the safety data 21.

Dose level 4 sits below dose level 3 in the cumulative window and above it at month 12. The month-12 figures cover only participants who completed 52 weeks: five of nine at dose level 4 and three of five at dose level 3. The two windows differ in both people and weeks, so neither ordering yet says much about dose response.

Encoded also reports gains in cognition and adaptive behaviour. In participants treated before age two, Bayley-4 cognitive scores diverged from the ENVISION natural history study with up to 76 weeks of follow-up. VABS-3 scores improved across all evaluated domains, which Encoded describes as clinically meaningful.

On safety, Encoded reports no treatment- or procedure-related serious adverse events across all four dose levels, with up to 117 weeks of follow-up. Treatment-related adverse events included transaminase elevations in 7 of 21 participants and thrombocytopenia in 3 of 21, both clinically asymptomatic and resolved in all participants.

What ETX101 is

ETX101 is an investigational AAV9-based gene regulation therapy, designed to increase expression of the SCN1A gene and restore sodium channel function in inhibitory interneurons. It is given once, by intracerebroventricular injection.

It holds FDA Breakthrough Therapy, RMAT, Fast Track, Rare Pediatric Disease and Orphan Drug designations, plus EMA Orphan designation. It was also selected for the FDA's CMC Development and Readiness Pilot, or CDRP.

Of that list, the CDRP selection bears most on this round. It is an FDA pilot on chemistry, manufacturing and controls (CMC) readiness, and this round will support manufacturing scale-up as well as trials.

What this means for a CGT program

GTC analysis: on CMC, the choice is when to pay. Encoded is paying for commercial manufacturing scale-up now, from this Series F, rather than leaving it to a raise after the readout.

GTC analysis: for a sponsor that uses a CDMO, the same decision arrives as a vendor question. When is the commercial site committed, and do pivotal lots come from it?

If you have planned a commercial manufacturing site around a pivotal study, GTC's Expert Network matches CMC experts like you to paid consulting work: join free.

GTC analysis: the two age ranges set the regulatory order. The pivotal study evaluates children aged 6 months to 4 years, while the expansion study runs up to age 18. If ETX101 is approved on the pivotal study, the youngest patients are the ones its evidence covers first, and older patients depend on what the expansion study adds.

GTC analysis: three figures would make this round a usable benchmark, and neither release gives them. They are the split of the round, a pivotal readout date and manufacturing capacity.

Frequently asked questions

How much did Encoded Therapeutics raise, and who led the round?

Encoded Therapeutics announced the close of a $275 million Series F financing on September 9, 2026. GV and another healthcare fund, not named in the announcement, co-led the round. 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 also took part.

What will the $275 million fund?

Encoded says the proceeds will support the pivotal study of ETX101 in infants and young children with SCN1A+ Dravet syndrome. They will fund an expansion study in children and adolescents up to 18 years of age as well. The funding will also support commercial scale-up of its internal GMP manufacturing and pipeline advancement, including ETX301 toward a 2027 IND submission for post-amputation neuroma pain. The announcement does not say how the money is split between these uses.

What is ETX101?

ETX101 is an investigational AAV9-based gene regulation therapy designed to increase expression of the SCN1A gene and restore sodium channel function in inhibitory interneurons. It is given as a single intracerebroventricular injection. It holds FDA Breakthrough Therapy, Regenerative Medicine Advanced Therapy, Fast Track, Rare Pediatric Disease and Orphan Drug designations, plus EMA Orphan designation. It was also selected for the FDA's CMC Development and Readiness Pilot program.

What did the latest POLARIS data show?

Encoded presented interim data at the 16th European Epilepsy Congress, with an August 3, 2026 cutoff. From week 5 through week 52 or the latest visit, the median reduction in monthly countable seizure frequency was about 76% at dose level 3 (n=5). At dose level 4 (n=9) it was about 60%. Among participants with 52 weeks of observation, the month-12 median reduction was about 79% at dose level 3 (n=3) and 89% at dose level 4 (n=5). Encoded reports no treatment- or procedure-related serious adverse events with up to 117 weeks of follow-up.

Where does the pivotal study stand?

The pivotal ENDEAVOR Part 2 study is ongoing, evaluating seizure and neurodevelopmental outcomes in children aged 6 months to 4 years. Encoded's CEO, Kartik Ramamoorthi, said the financing gives the company the resources to advance ETX101 toward registration. Neither of the two September releases reports pivotal results.

Sources

Dr. Rahul Kaushik

Dr. Rahul Kaushik

Founder & CEO, Gene Therapy Consultancy

Gene therapy expert and neuroscientist with over 10 years of experience in viral vector-based gene delivery. He founded Gene Therapy Consultancy to help biotech teams navigate the path from promising science to approved therapies.

Avoidable Hurdles: anything that could have been avoided — if only you had known about it sooner. GTC helps biotech teams, investors, technology developers, vendors and suppliers, and CDMOs and CROs navigate the path from promising science to approved therapies.

Why GTC

Everyone who needs help and everyone who can help, in one place, to remove the avoidable hurdles.

Real-world experts, pooling what they have already lived through, shaped to your situation. The right help at the right time, so you get the best outcome in the least time and money.

How GTC can help
  • CGT drug developers — plan a route to IND submission that fits the funding you already have, staged so each step has a go/no-go before you spend on the next, without building an expensive in-house team.
  • CGT investors — judge an asset with a real due-diligence framework, without building one yourself, and help portfolio companies burn less cash.
  • Technology developers — find out how the people who would run your tool actually work today, before you build for a use case they do not have.
  • Vendors and suppliers — understand why programmes standardise on what they standardise on, straight from the teams making that call.
  • CDMOs and CROs — learn what developers screen for when they build a shortlist, from the people who build them.
What you can do — all free
  •   Connect on LinkedIn Where the analysis goes out first.
  •   Book a Free Discovery Call No cost. If it goes further, we put an NDA in place first.
  •   Subscribe to AAV to AI CGT deals, trial data and funding news.
  • Join the GTC Expert Network Download everything the experts have built, tell us what you want covered, and we get you the information when you need it. 250+ experts and industry representatives are onboarding right now.

Join the GTC Expert Network

Independent Experts

Independent experts in cell & gene therapy: share knowledge, help build a report, or contribute quietly. Build authority and get called for paid consulting work. Join free.

Early R&D Experts

Early R&D Experts

Contribute target validation, vector engineering, or transgene design expertise. Get matched to paid consulting work through content you help create.

Join Free

CMC Experts

CMC Experts

Contribute scale-up, tech transfer, or GMP manufacturing expertise. Get matched to paid consulting work through content you help create.

Join Free

Regulatory Affairs Experts

Regulatory Affairs Experts

Contribute IND/BLA strategy or regulatory liaison expertise. Get matched to paid consulting work through content you help create.

Join Free

Commercial & Strategy Experts

Commercial & Strategy Experts

Contribute due diligence, licensing, or market access expertise. Get matched to paid consulting work through content you help create.

Join Free

Enabling Technology Experts

Enabling Technology Experts

Contribute bioprocessing hardware, analytical tooling, or supply-chain expertise. Get matched to paid consulting work through content you help create.

Join Free

AI Transformation Experts

AI Transformation Experts

Contribute agentic workflow, LLM, or AI-driven vector design expertise. Get matched to paid consulting work through content you help create.

Join Free

Industry Representatives

Industry professionals in cell & gene therapy: de-risk your pipeline with expert input on demand, exactly when your program needs it. Join free.

Drug Developers

Drug Developers

Founders, CSOs, VPs of R&D

Practical guides spanning vector design through commercialization, plus direct access to the expert network that wrote them.

Join Free

Investors / VCs

Investors / VCs

VC Fund Managers, Family Offices, Angels

Due diligence frameworks and strategic intelligence for evaluating CGT assets, from experts who do this diligence for a living.

Join Free

Technology Developers

Technology Developers

Founders, Licensing & Commercial Leads

IP protection and platform strategy guides for enabling technologies, plus the network that built them.

Join Free

CDMOs / CROs

CDMOs / CROs

BD, Operations & Technical Leads

Partner selection, vendor evaluation, and operational excellence guides, sourced from the CGT organisations that use them.

Join Free

Vendors / Suppliers

Vendors / Suppliers

Commercial & Technical Leads

Market intelligence and partnership strategies for supply chain companies serving cell and gene therapy.

Join Free

Strategy Consultants

Strategy Consultants

Consultants, Market Access Advisors

Spot the problems before they cost your clients — join the network that shapes what GTC covers next.

Join Free

AI Transformation Partners

AI Transformation Partners

AI/ML Consultancies, Digital Transformation Firms

AI education, implementation, and consulting for operational excellence in cell and gene therapy — for companies building or buying AI capability.

Join Free

Where the analysis comes from. Industry teams get expert input on demand; independent experts build authority and get called for paid consulting work.

See more of our work in Google Search

Google lets you pick the sites you want to see more often in Top Stories. Add Gene Therapy Consultancy to your list, and our daily gene therapy news will show up higher for you.

Follow us on Google