What are the major technical and regulatory challenges in bringing CRISPR therapies to clinical trials?

Technical challenges include: ensuring high on-target efficiency with minimal off-target effects (requiring comprehensive genome-wide analysis like GUIDE-seq or DISCOVER-seq), achieving therapeutic delivery to target tissues (especially systemic delivery beyond liver), managing immunogenicity against Cas proteins and delivery vehicles, controlling genotoxicity from double-strand breaks, and ensuring durable therapeutic effect. Regulatory challenges include demonstrating product consistency, developing sensitive detection assays for rare events, establishing appropriate potency assays, addressing long-term safety monitoring, and navigating germline editing prohibitions. Manufacturing challenges include scaling GMP-grade production of editing components (viral vectors, RNPs, mRNA-LNPs) while maintaining quality and sterility.