Soufflé Therapeutics closed an oversubscribed $135 million Series B financing on 13 October 2026, the Boston-area RNA-therapeutics company announced, to fund its first clinical trials across three programs built on a delivery platform designed to reach cells beyond the liver — a target most RNA-drug technologies still struggle to hit efficiently. Juvia Group led the round, with 17 other new and existing investors named.
Soufflé's Series B, in four figures
Figures from Soufflé's own 13 October 2026 financing announcement and independent trade coverage.
A delivery problem RNA drugs haven't solved
Most approved RNA-interference drugs reach only one organ well: the liver, thanks to a conjugate chemistry (GalNAc) that targets liver cells efficiently. Soufflé Therapeutics was built around a different bet — that siRNA and other oligonucleotide drugs could reach muscle, heart and other tissue types if paired with the right cell-surface receptor and the right binder to grab it. The company calls its platform REMEDY, for Receptor Mediated Delivery: it says the approach systematically screens for internalizing receptors on a target cell type, then builds a proprietary binder, often a monoclonal antibody, to carry the RNA payload inside.
Three things REMEDY is being asked to prove
Delivery outside the liver
Soufflé's entire pipeline depends on REMEDY successfully delivering RNA payloads to skeletal muscle (SFL-0821) and cardiomyocytes (the PLN program) — cell types that have been far harder to reach than the liver, where most approved siRNA drugs work.
A crowded, not empty, target
SFL-0821 targets DUX4, the gene whose aberrant expression in skeletal muscle is understood to drive FSHD, a muscular dystrophy with no FDA-approved disease-modifying treatment today — but Soufflé is not alone there: Avidity Biosciences' own DUX4-targeting conjugate, del-brax, is already in Phase 1/2 testing with reported positive interim data, well ahead of Soufflé's still-preclinical program.
Pharma is paying before data exists
Bayer's January 2026 collaboration and the Series B's roster of both existing and new institutional investors committed capital and partnership terms before any of Soufflé's three lead programs had entered a clinical trial, according to the company's own financing announcement.
What $135 million buys before a single trial starts
Soufflé's own announcement frames the financing around a particular milestone: moving its most advanced program, not yet named in detail beyond SFL-0821 targeting FSHD, into its first clinical study. The company says proceeds will fund first-in-human studies across all three named programs — FSHD, heart failure and the undisclosed muscle and metabolic candidate — plus continued preclinical work behind them. None of the three had dosed a patient as of the financing's announcement, a detail that puts Soufflé earlier in its lifecycle than most companies raising at this scale.
“We are honored and grateful for this vote of confidence from both new and existing investors as we advance our first program into the clinic.” Amir Nashat, Ph.D., Chief Executive Officer, Soufflé Therapeutics — 13 October 2026 announcement
The RNA-delivery field Soufflé is betting against
$19.2B → $31.1B
Global RNA therapeutics market, 2023 actual to 2032 forecast, per Global Market Insights; MarketsandMarkets puts it lower, at $13.7B (2023) to $18.0B by 2028.
Sources: Global Market Insights, RNA Therapeutics Market report · MarketsandMarkets, RNA Therapeutics Market report (lower, divergent estimate)
Regulatory News outlook
We read Soufflé's bet as a wager on the extra-hepatic slice of that RNA-therapeutics forecast specifically: the company is not competing for the liver-targeted GalNAc-siRNA share most approved RNA drugs already occupy, but for indications, like FSHD, where no RNA drug of any delivery type has reached patients yet.
How we got here: No new figure is computed; Global Market Insights' published $19.2 billion (2023) to $31.1 billion (2032) RNA-therapeutics forecast is cited as the category Soufflé competes within, without attempting to isolate an extra-hepatic-delivery sub-figure that no cited publisher reports separately. MarketsandMarkets' lower, differently scoped estimate is shown alongside it rather than silently dropped.
Soufflé against RNA delivery's other approaches
| Company | Delivery approach | Primary target tissue | Clinical status |
|---|---|---|---|
| Soufflé Therapeutics (REMEDY) | Receptor-targeted antibody-siRNA conjugates | Skeletal muscle, cardiomyocytes | Preclinical; first trials funded by this round |
| Alnylam Pharmaceuticals (GalNAc-siRNA) | GalNAc-conjugate siRNA | Liver | Multiple approved products |
| Dicerna / Novo Nordisk (GalXC) | GalNAc-conjugate siRNA | Liver | Approved and clinical-stage products |
| Avidity Biosciences (del-brax / AOC 1020) | Antibody-oligonucleotide conjugate, also targets DUX4 | Skeletal muscle | Phase 1/2, reported positive interim data |
From each company's own disclosures and published pipelines; not a clinical comparison. Avidity Biosciences (Nasdaq: RNA) is developing its own DUX4-targeting antibody-oligonucleotide conjugate for FSHD and has already reported Phase 1/2 mobility and strength data; Soufflé's SFL-0821 remains preclinical by comparison.
From an MIT lab to a second oversubscribed round
Soufflé's road to a $135 million Series B
- Founding
Soufflé Therapeutics founded
Co-founded by MIT's Robert Langer alongside Daniel Anderson, Marino Zerial, Brad Pentelute and Victor Kotelianski, with Amir Nashat as chief executive, to build the REMEDY delivery platform.
- October 2025
$200 million Series A
The company closes a $200 million Series A financing round to build out its receptor-delivery platform and pipeline.
- January 2026
Bayer collaboration
Soufflé and Bayer announce a strategic collaboration to develop a cell-specific, heart-targeted siRNA therapy for a form of dilated cardiomyopathy.
- 13 October 2026
$135 million Series B closed
Juvia Group leads an oversubscribed Series B, with 17 other investors named, to fund first clinical trials in FSHD, heart failure and a third muscle and metabolic program.
- Ahead
A first patient to dose
Soufflé has not stated a filing or dosing date for SFL-0821's first clinical trial; the Series B is explicitly meant to fund it.
What this financing does not resolve: Soufflé has not filed an IND or announced a clinical-trial start date for any of its three named programs, so FSHD patients and their physicians have no near-term timeline to track yet. The company's own disclosures do not break out how the $135 million splits across its three programs, and no third-party source independently verifies Soufflé's total funding to date beyond the two named rounds.
- Financing: $135 million Series B, oversubscribed, closed 13 October 2026, led by Juvia Group.
- Pipeline: SFL-0821 (FSHD), a PLN-targeting siRNA (heart failure with reduced ejection fraction), and an undisclosed muscle and metabolic program — all preclinical as of this financing.
- Validation: a January 2026 collaboration with Bayer on a separate heart-targeted siRNA program.
- Not yet public: a clinical-trial start date for any named program, and a per-program breakdown of how the new funding will be spent.
Sources & further reading
- BioSpace (press release), "Soufflé Therapeutics Announces Oversubscribed $135 Million Series B Financing to Advance Lead Clinical Programs and Continued Pipeline Progress," 13 October 2026. biospace.com
- Endpoints News, "Soufflé gets $135M for three RNA medicines." endpoints.news
- FinSmes, "Soufflé Therapeutics Raises $135M in Series B Funding." finsmes.com
- Dealroom, "Soufflé Therapeutics raises $135M Series B to take RNA therapies into the clinic." dealroom.co
- Bayer, "Advancing Cell-Specific, Heart-Targeted siRNA Therapy," 7 January 2026. bayer.com
- Precedence Research, RNA Therapeutics Market report. precedenceresearch.com
Regulatory News reports on public regulatory documents. It is not legal advice, and the primary sources above govern. If we have made an error, we will say so in public: see corrections.
Frequently asked questions
How much did Soufflé Therapeutics raise, and from whom?
An oversubscribed $135 million Series B, announced 13 October 2026, led by Juvia Group with 17 other investors named, including new backers TCG Crossover Management, BB Biotech, Fidelity Management & Research, Balyasny Asset Management and a sovereign wealth fund, plus existing investors Amgen Ventures, ARCH Venture Partners, Leaps by Bayer and others. It follows a $200 million Series A in October 2025.
What will the money fund?
Soufflé's first clinical studies in three programs: SFL-0821 for facioscapulohumeral muscular dystrophy (FSHD), a PLN-targeting siRNA for heart failure with reduced ejection fraction, and an undisclosed muscle and metabolic program, plus continued preclinical work.
Is Soufflé a public company?
No. It is privately held, backed by venture and crossover investors. This financing does not create a public listing, a stock symbol or a live share price.
What is REMEDY?
Soufflé's name for its delivery platform, which the company says identifies receptors on specific cell types and builds proprietary binders, including monoclonal antibodies, to carry oligonucleotide drugs into cells outside the liver — a target other RNA-delivery technologies have struggled to reach efficiently.
