ARCUS is a novel, highly precise and versatile genome editing technology for DNA genome insertion, deletion, and repair

ARCUS is a proprietary genome editing technology discovered by scientists at Precision BioSciences. We currently have multiple allogeneic, “off-the-shelf” CAR T immunotherapies in early-stage clinical trials with other in vivo gene editing programs in late-stage preclinical development.

ARCUS is based on a naturally occurring genome editing enzyme, I-CreI, that evolved in the algae Chlamydomonas reinhardtii to make highly specific cuts and DNA insertions in cellular DNA. I-CreI is a member of a larger class of enzymes called homing endonucleases or meganucleases.

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Gene Therapy vs. Cancer Immunotherapy Chart

The ARCUS Advantage – Designed for Therapeutic Applications

The ARCUS platform is designed to deliver therapeutic-grade genome editing. In contrast to editing platforms that focus on ease of design and quick turnaround, ARCUS is a potentially safer and more precise editing approach because of its precision and versatility.

An ARCUS nuclease is only active in the presence of its desired target DNA site. It is otherwise inactive until it engages with its target site, further increasing the efficiency of on-target edits and minimizing potential for off-targeting. What makes ARCUS versatile? Its small size makes it easier to deliver using either adeno–associated virus (AAV) vectors or lipid nanoparticles (LNPs) to specific tissues and cells.

What differentiates ARCUS genome editing?


Our platform and products, including ARCUS nucleases are protected by a comprehensive IP portfolio with more than 95 patents to date.


ARCUS isn’t limited to deletions. ARCUS can perform complex edits, including gene insertion, gene repair, and gene deletions.


ARCUS doesn’t generate truly random DNA breaks. ARCUS is only active in the presence of its desired target DNA site.


ARCUS is one-fifth the size of CRISPR Cas9 and compatible with essentially any delivery strategy.

One Polypeptide

ARCUS is a single protein expressed from a single gene. There’s no need to deliver multiple parts. This enables efficient multiplexing of edits.


Matched 4 base pair 3′ overhangs result in predictable and detectable removal of DNA.