Infinimmune Raises $75 Million Series A to Advance Fully Human Antibody Therapies

Alameda, California-based biotechnology company Infinimmune has raised $75 million in Series A funding to advance its pipeline of fully human antibody therapeutics.

The round was co-led by Regeneron Ventures and Playground Global, with participation from RA Capital Management, Goldcrest Capital, Forge Life Science Partners, Godfrey Capital, Wild Tree Ventures, Merck Global Health Innovation Fund, Everbright Biofund, Civilization Ventures and Pear VC.

The fresh capital will support the clinical development of Infinimmune’s two lead antibody programs, IFX-101 and IFX-201, which target atopic dermatitis. The company plans to begin Phase 1 human testing in 2027, while continuing to develop additional antibody candidates using its human immune system-based discovery platform.

Funding Snapshot

About Infinimmune

Founded by a team with expertise in immunology, genomics, artificial intelligence and drug development, Infinimmune develops fully human antibodies derived directly from the human immune system.

The company’s platform screens millions of single memory B cells across hundreds of targets to identify naturally paired antibodies. Its GLIMPSE antibody language models are then used to help select and optimize promising candidates.

Core offerings include:

• Fully human antibody discovery
• AI-assisted antibody selection
• Therapeutic antibody development
• Human B-cell screening technology

Infinimmune aims to identify antibodies with strong potency, specificity, developability and longer half-lives, potentially enabling less frequent dosing.

Lead Drug Candidates

IFX-201 targets IL-13, a clinically validated pathway in atopic dermatitis. The program is intended to potentially offer an alternative approach for patients who may not respond adequately to existing treatments.

IFX-101 targets IL-22, a pathway that Infinimmune describes as an important but underexplored component of eczema biology. There is currently no approved biologic specifically targeting IL-22 for atopic dermatitis.

Both programs are expected to enter Phase 1 testing in 2027.

Previous Funding & Investors

The latest Series A follows earlier backing from investors including Merck & Co. In March 2026, Merck entered into a partnership with Infinimmune valued at up to $838 million in potential payments, focused on antibody discovery and development.

Funding Timeline