RegCell Raises $66M for Nobel-Backed Treg Therapy

RegCell has raised $66 million in combined new capital — a $44 million Series A led by Playground Global and a second non-dilutive grant of ¥3.4 billion (about $22 million) from Japan’s Agency for Medical Research and Development — to fund an FDA investigational new drug application and push a second autoimmune-disease program toward human proof-of-concept. The Emeryville, California company announced the financing on 15 September 2026, building on a platform whose scientific foundation belongs to a discovery that won its founder a Nobel Prize eleven months earlier.

Thirty years from one paper to a term sheet

RegCell traces its science to a single discovery: in 1995, immunologist Shimon Sakaguchi identified regulatory T cells, or Tregs — a subset of immune cells that suppress the body’s attacks on its own tissue rather than triggering them. That finding sat at the center of immunology for three decades before the company built around it existed. RegCell was founded in Osaka, Japan in January 2016 to turn Sakaguchi’s Treg biology into a therapy, and in March 2025 completed a transition of its U.S. headquarters to Emeryville, California alongside an earlier $45.8 million financing.

From an Osaka lab to a second AMED grant

1. 1995

   Sakaguchi identifies regulatory T cells

   The foundational discovery, decades later shared by the Nobel committee with Mary E. Brunkow and Fred Ramsdell for related work on immune tolerance.

2. January 2016

   RegCell founded

   Founded in Osaka, Japan, to develop antigen-specific Treg cell therapies from Sakaguchi’s research.

3. March 2025

   $45.8 million raised; U.S. HQ established

   An $8.5 million seed equity round plus RegCell’s first AMED grant (up to ¥5.6 billion) funds a U.S. headquarters transition to Emeryville, California.

4. October 2025

   Sakaguchi wins the Nobel Prize

   The Nobel Prize in Physiology or Medicine is awarded to Sakaguchi, Brunkow and Ramsdell for discoveries concerning regulatory T cells.

5. 15 September 2026

   $66 million Series A and second AMED grant close

   Funds an FDA IND submission and a second autoimmune indication for the next-generation platform.

6. Not yet dated

   IND submission

   No filing date has been disclosed.

Reprogramming the cells that attack, not calming them

RegCell’s platform takes a patient’s own T cells — including the disease-causing ones driving an autoimmune attack — and uses an epigenetic reprogramming process, rather than gene editing, to convert or stabilize them into functional, antigen-specific Tregs. The company frames this as a way to suppress the specific autoimmune response at its source instead of broadly dampening the immune system the way most current autoimmune drugs do. The approach has been advancing toward clinical proof-of-concept in autoimmune liver disease on RegCell’s first-generation platform; this financing funds a second, not-yet-named autoimmune program built on a next-generation version of the platform.

“We believe that patients need better options than what current autoimmune therapies provide. By reprogramming disease-causing T cells into stable, antigen-specific regulatory T cells, we are now able to target and suppress the root causes of autoimmunity rather than broadly suppressing the immune system, opening the door to truly disease-specific immunotherapies.” Dr. Michael V. McCullar, President and Chief Executive Officer, RegCell — 15 September 2026 announcement

RegCell’s raise, in four numbers

$66Mcombined financing: a $44 million Series A plus a second, roughly $22 million AMED grant

2ndnon-dilutive AMED grant RegCell has received, after a first award of up to ¥5.6 billion in March 2025

1995the year Shimon Sakaguchi’s foundational Treg discovery was published, three decades before this raise

2025the year Sakaguchi won the Nobel Prize in Physiology or Medicine for that work

Figures from RegCell’s public announcements and the Nobel Foundation.

Three bets behind the $66 million

01

A Nobel Prize under the science

RegCell’s scientific founder won the 2025 Nobel Prize in Physiology or Medicine for the Treg biology the platform is built on — a credibility marker few cell therapy startups can claim.

02

No gene editing

The platform reprograms a patient’s own T cells epigenetically rather than through gene engineering, which the company positions as a simpler manufacturing and regulatory path than engineered CAR-Treg approaches.

03

Two disease programs, one platform

A first-generation program in autoimmune liver disease is already advancing toward clinical proof-of-concept; this raise funds a second, next-generation program in an as-yet undisclosed autoimmune indication.

An autoimmune market Tregs have barely touched

Autoimmune disease is not a niche market. Most current treatments — steroids, biologics that block a single inflammatory pathway, broad immunosuppressants — manage symptoms rather than restore the immune system’s own tolerance mechanisms. Cell therapies designed to rebuild that tolerance, RegCell’s included, are still years from a first approval anywhere in the category.

Autoimmune therapeutics, two forecasts to 2030

$231B → $336B

Global autoimmune disease therapeutics market, 2025 to 2030, per 360iResearch; a separate Market Research Future forecast puts a narrower slice of the market at $150B by 2030.

2025 (360iResearch)$231.2B

2030 (360iResearch)$336.3B

2030 (MRFR, narrower scope)$150.3B

Sources: 360iResearch, Autoimmune Disease Therapeutics Market Size 2025-2030 · Market Research Future, Autoimmune Disease Treatment Market Report

Regulatory News outlook

We expect Treg cell therapies to remain a rounding error against these totals until a first approval anywhere in the category, since no Treg-based product — RegCell’s included — has yet reached an FDA filing.

How we got here: The published forecasts already span a $150 billion to $336 billion range for 2030 depending on scope; we treat cell therapies restoring immune tolerance, rather than suppressing it, as a small and currently unpriced slice of that range until clinical data exists to size it.

RegCell against other tolerance-restoring cell therapies

Company	Approach	Lead focus	Stage
RegCell	Epigenetically reprogrammed, antigen-specific Tregs from a patient’s own T cells; no gene editing	Autoimmune liver disease (first-generation); a second, undisclosed indication (next-generation)	Preclinical/IND-enabling; IND not yet submitted
Sonoma Biotherapeutics	Engineered Treg cell therapy	Inflammatory bowel disease and other autoimmune indications	Clinical-stage
Quell Therapeutics	Engineered CAR-Treg cell therapy	Transplant tolerance and inflammatory bowel disease	Clinical-stage
Abata Therapeutics	Antigen-specific Treg cell therapy	Progressive multiple sclerosis and type 1 diabetes	Clinical-stage

From each company’s own public program descriptions; not a head-to-head clinical comparison.

Two funding rounds, zero human data so far

RegCell has now raised roughly $112 million in disclosed financing across two rounds — the $45.8 million secured in March 2025 and this $66 million round — without yet reporting Treg reprogramming data in a dosed human patient. The company says the new financing will fund exactly that: an FDA IND submission and the generation of human proof-of-concept data, plus a manufacturing partnership with Kincell Bio for process development and GMP-scale production to support IND-enabling work. Neither an IND filing date nor the name of the second autoimmune indication has been disclosed.

• Investors: Playground Global led the $44 million Series A, joined by new investors Global Brain, Mitsui Chemicals, LG Technology Ventures, Alumni Ventures and Medical Incubator Japan, alongside existing investors Fast Track Initiative, UTEC, Osaka University Venture Capital and Kyoto University Innovation Capital.
• Manufacturing: RegCell has partnered with Kincell Bio for process and analytical development and scalable GMP manufacturing to support IND-enabling activities.
• Not yet public: RegCell has not disclosed an IND filing date, the name of the second autoimmune indication this raise funds, or a post-money valuation for the round.

Frequently asked questions

How much did RegCell raise, and from whom?

$66 million in combined new capital, announced 15 September 2026: a fully subscribed $44 million Series A led by Playground Global, with new participation from Global Brain, Mitsui Chemicals, LG Technology Ventures, Alumni Ventures and Medical Incubator Japan alongside existing investors Fast Track Initiative, UTEC, Osaka University Venture Capital and Kyoto University Innovation Capital — plus a second non-dilutive grant of ¥3.4 billion (about $22 million) from Japan’s Agency for Medical Research and Development (AMED).

What will the money fund?

RegCell says the combined financing will support an FDA investigational new drug (IND) application submission, generation of human proof-of-concept data, and advancing its next-generation epigenetic reprogramming platform into a second autoimmune indication through a Phase 2 proof-of-concept study. The company has not disclosed a filing date.

What is RegCell's connection to a Nobel Prize?

RegCell's scientific founder and board member, Dr. Shimon Sakaguchi, was awarded the 2025 Nobel Prize in Physiology or Medicine, shared with Mary E. Brunkow and Fred Ramsdell, for discoveries concerning regulatory T cells (Tregs) — the immune “peacekeeper” cells his research first identified in 1995 and that RegCell’s platform is built to reprogram.

Has RegCell tested its therapy in patients yet?

Not yet disclosed as reaching human dosing. The company’s first-generation platform, funded by an earlier AMED grant and a 2025 seed round, has been advancing toward clinical proof-of-concept in autoimmune liver disease; this new financing funds the IND submission and a second, not-yet-named autoimmune indication for the next-generation platform.