CTX310

August 28, 2026: CRISPR Therapeutics (NASDAQ: CRSP) reported late-breaking ESC Congress 2026 and simultaneous NEJM publication of one-year Phase 1a durability data for CTX310, an in vivo CRISPR/Cas9 therapy targeting ANGPTL3 for lipid disorders including HoFH, HeFH, severe hypertriglyceridemia, and mixed dyslipidemias.

In the open-label dose-escalation Phase 1a study, 15 participants received a single IV dose of 0.1-0.8 mg/kg and all had at least one year of follow-up. At the highest dose (0.8 mg/kg), CTX310 showed sustained, dose-dependent reductions with mean decreases from baseline of 79% in circulating ANGPTL3, 48% in triglycerides, and 53% in LDL; maximum reductions were 89%, 78%, and 84%, respectively.

Safety remained favorable: no treatment-related serious adverse events, no dose-limiting toxicities, no Grade 3 or higher liver transaminase changes, and no new treatment-related safety events during extended follow-up. Previously reported events included one allergic reaction that resolved with supportive care and three Grade 2 infusion-related reactions.

CRISPR said Phase 1b is ongoing in the U.S. and outside the U.S. using a fixed dose equivalent to the most efficacious Phase 1a dose, with an update expected in 2H 2026 focused on severe hypertriglyceridemia patients.