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Accipiter Biosciences

Computationally designed proteins that hit several targets

Raised to date

$10.5M

of $10.5M offered across 1 Form D filing

Investors
9
Last filed
Jul 28, 2026

About

Accipiter Biosciences is a Seattle-based biotechnology company designing de novo multifunctional protein therapeutics for complex diseases including autoimmune disorders and cancer. It uses computational and machine-learning protein design to build single biologics that engage several cellular targets or pathways at once, rather than combining multiple drugs. The company emerged from stealth in November 2025 with $12.7 million in seed financing co-led by Takeda and Flying Fish Partners, and has announced partnerships with Pfizer and Kite Pharma. Its founding team includes researchers from the University of Washington's Institute for Protein Design.

Its de novo proteins are not constrained by natural antibody scaffolds, so they can act as agonists as well as blockers and combine multiple mechanisms in one molecule, with a design-to-lab-testing cycle the company puts at under two months.

Funding

  • EquityFiled Jul 28, 2026Form D
    $10.5M/ $10.5M

Product

De novo multifunctional biologics platform

Drug discovery platform / preclinical biologics

A computational protein design platform that generates entirely new protein sequences, synthesizes and purifies them in the lab, and tests them functionally in cell and animal models, producing single-agent biologics that engage multiple pathways.

  • De novo protein design not bound by natural antibody structures
  • Multifunctional molecules that engage several targets or pathways at once
  • Can produce agonists that activate pathways, not only blockers

Built for

Pharmaceutical and biotech partners licensing or co-developing designed biologics, and ultimately patients with complex autoimmune and oncology indications

People on file