# Third Arc Bio

Startup profile on Capital Atlas: https://capitalatlas.ai/startups/third-arc-bio

- Industry: Biotechnology
- Headquarters: Boston, US
- Website: www.thirdarcbio.com/
- Total disclosed funding: $125M
- Latest round: Series A (Feb 4, 2026)
- Investors on record: 16

## About

Based in Pennsylvania, US, and founded in 2021 by Sanjaya Singh, Third Arc Bio, Inc. is a biotech company that focuses on developing multifunctional antibodies that are optimized for best-in-class T cell engagement across solid tumors and inflammatory and immunology diseases. In February 2026, Third Arc Bio, Inc. raised USD 52 million in series A funding led by new investor Andreessen Horowitz, with participation from other new investor Galapagos NV. Returning investors Goldman Sachs Asset Management, BVF Partners, T. Rowe Price Associates, Janus Henderson Investors, Marshall Wace, Foresite Capital, Logos Capital, Freepoint Capital Group, and AbbVie Ventures, Omega Funds, Vida Ventures, Cormorant Asset Management, Hillhouse Investment, and Alderline Group also participated in the round. The round was a part of larger USD 217 million series A funding. As of 2026 the company is headed by its CEO Peter F. Lebowitz.

Third Arc Bio specializes in the development of multifunctional antibodies designed to create immune synapses that precisely activate or inhibit T cells. The company's therapies are targeted at treating solid tumors and inflammatory and immunological (I&I) diseases. Through its expertise in immunology and antibody engineering, Third Arc Bio aims to advance next-generation biologic treatments that could redefine the standard of care in these therapeutic areas. The company’s solutions are focused on enhancing the immune response to treat complex diseases by optimizing T cell activity, offering a potential breakthrough in the treatment of challenging conditions.

The company will use the February 2026 funding to expand its oncology, immunology and inflammation drug portfolio and advance existing drug candidates into early clinical studies.

## Funding rounds

- Series A, Feb 4, 2026, $52M — T Rowe Price, Marshall Wace, Andreessen Horowitz, Omega Funds, Goldman Sachs Asset Management, Hillhouse Investment, Foresite Capital, Galapagos NV, AbbVie Ventures, BVF Partners, Cormorant Asset Management, Janus Henderson Investors, Vida Ventures, Logos Capital, Freepoint Capital Group, Alderline Group
- Series A, Jul 16, 2024, $73M — Marshall Wace, Omega Funds, Goldman Sachs Asset Management, Hillhouse Investment, Foresite Capital, AbbVie Ventures, BVF Partners, Cormorant Asset Management, Janus Henderson Investors, Vida Ventures, Logos Capital, Freepoint Capital Group
- Seed, Jun 1, 2022 — Omega Funds

## Investors

- Omega Funds (https://capitalatlas.ai/funds/omega-funds) — Seed, Series A
- Marshall Wace (https://capitalatlas.ai/funds/marshall-wace) — Series A
- Goldman Sachs Asset Management (https://capitalatlas.ai/funds/goldman-sachs-asset-management) — Series A
- Hillhouse Investment (https://capitalatlas.ai/funds/hillhouse-investment) — Series A
- Foresite Capital (https://capitalatlas.ai/funds/foresite-capital) — Series A
- AbbVie Ventures (https://capitalatlas.ai/funds/abbvie-ventures) — Series A
- BVF Partners (https://capitalatlas.ai/funds/bvf-partners) — Series A
- Cormorant Asset Management (https://capitalatlas.ai/funds/cormorant-asset-management) — Series A
- Janus Henderson Investors — Series A
- Vida Ventures (https://capitalatlas.ai/funds/vida-ventures) — Series A
- Logos Capital (https://capitalatlas.ai/funds/logos-capital) — Series A
- Freepoint Capital Group — Series A
- T Rowe Price (https://capitalatlas.ai/funds/t-rowe-price) — Series A
- Andreessen Horowitz (https://capitalatlas.ai/funds/andreessen-horowitz) — Series A
- Galapagos NV — Series A
- Alderline Group (https://capitalatlas.ai/funds/alderline-group) — Series A