About ai3Bio
ai3Bio is a biotechnology company developing treatments for autoimmune disease. It points to more than 15 million Americans living with these conditions. Its view is that current therapies calm the immune system broadly or block inflammatory chemicals, while the disease-causing cells stay in the body. ai3Bio targets Th17 cells directly. Its AI platform analyzed diseased tissue and found a marker these cells share across many conditions. The STARx platform delivers mRNA inside a lipid nanoparticle, and the mRNA prompts Th17 cells to self-destruct. The T Deplete platform uses a targeting antibody that recruits the body's own immune cells to clear them.
ai3Bio is based in Watertown, Massachusetts, with a second office in Pittsburgh, Pennsylvania. It launched on September 29, 2026, announcing a $48 million Series A. UPMC Enterprises and Ziff Capital Partners led the round, and Cockrell Interests and Tanis Ventures took part. Steven Altschuler is chief executive officer. Jonathan Kagan of Harvard Medical School and Boston Children's Hospital is scientific co-founder. Michael Lyman serves as chief technology officer. Nick Seaver serves as chief financial and business officer. In lab tests on blood from autoimmune patients, STARx cleared disease-causing Th17 cells. T Deplete showed strong efficacy in non-human primates and has moved into the safety studies needed before human trials.
Funding Rounds (SEC Form D)
| First sale | Filed with SEC | Amount sold | Investors | Avg. check | Terms | Filing |
|---|---|---|---|---|---|---|
| Sep 26, 2025 | Oct 20, 2025 | $16,754,446fully sold | 4 | $4.1M | Debt, Options, Securities on exerciseRule 506(b) | Form D ↗ |
| May 31, 2023 | Apr 23, 2024amended Aug 11, 2025 | $58,510,656of $63.4M target | 14 | $4.1M | EquityRule 506(b) | Form D/A ↗2 earlier filings |
| Total, two offerings | $75,265,102 | |||||
First sale is the date the first investor in the offering committed to invest. Companies must file Form D within 15 days of that date, so filing dates run later.
Rounds announced by ai3Bio
What the company said publicly about its funding. Announced amounts can differ from Form D figures: an announcement can combine several closings, and some money is raised without a Form D.
| Announced | Round | Amount | Investors | Source |
|---|---|---|---|---|
| Sep 29, 2026 | Series A | $48 million | UPMC Enterprises and Ziff Capital Partners (co-leads), Cockrell Interests and Tanis Ventures | ai3Bio press release ↗ Business Wire release ↗ |
Why Investors Backed ai3Bio
ai3Bio is a Watertown, Massachusetts, biotechnology company building therapies that aim to eliminate the T cells driving autoimmune disease. It launched on September 29, 2026, after raising $48 million in a Series A round, with UPMC Enterprises and Ziff Capital Partners as lead investors. ai3Bio's case is that removing the disease-causing cells directly could give patients lasting remission instead of a lifetime of symptom management. Its two platforms, STARx and T Deplete, are still in preclinical and early safety testing.
Progress so far
BioPharma Dive reported that ai3Bio was built from two biotechs and launched on September 29, 2026. BioWorld described the company's aim of a one-step solution that resets the immune system. PharmaVoice described ai3Bio's work as preclinical programs designed to eliminate disease-driving T cells in autoimmune conditions.
Who backs it
UPMC Enterprises and Ziff Capital Partners led the Series A. Both are founding investors that backed the technologies later combined to create ai3Bio. Cockrell Interests and Tanis Ventures also supported the round. The board includes chief executive officer Steven Altschuler, chief financial and business officer Nick Seaver, board chairman Fabian Tenenbaum, Jeanne Cunicelli, and Alan Ezekowitz.
How the market is moving
ai3Bio's case is that current therapies leave disease-causing cells in place and that a newer wave of in vivo therapies mostly targets B cells. Its view is that many autoimmune diseases are driven largely by T cells. ai3Bio's release puts the global market for autoimmune treatment above $130 billion. BioPharma Dive noted that many other emerging autoimmune drugs deplete B cells, while ai3Bio's therapies aim at Th17 cells instead.
We wrote this summary from public statements by ai3Bio and its investors. It is not investment advice.
ai3Bio in the News
Leadership Team
Executive officers and directors listed on ai3Bio's Form D filed Oct 20, 2025.
Earlier filings also listed Michael Lyman (executive officer, last listed Nov 2026), Jeanne Cunicelli (director, last listed Nov 2026) and Fabian Tenenbaum (director, last listed Nov 2026).