Prime Medicine, Inc. announced the publication of Phase 1/2 clinical data with PM359, the Company's investigational autologous hematopoietic stem cell product for p47phox chronic granulomatous disease (CGD) in the New England Journal of Medicine (NEJM). The data will also be presented in a poster session at the 67thAmerican Society of Hematology (ASH) Annual Meeting, December 6-9, 2025 in Orlando, Florida. The publication, titled "Prime Editing for p47-phox Chronic Granulomatous Disease," reports initial data for two patients treated in the Phase 1/2 trial of PM359, which was designed to assess safety, biological activity and preliminary efficacy in adult and pediatric study participants.
Both patients experienced rapid neutrophil and platelet engraftment, as well as durable restoration of NADPH oxidase activity and early clinical benefit, without any safety concerns. Together, these results provide the first-in-human demonstration of the safety and efficacy of Prime Editing, and support the potential for PM359 as a precise therapeutic strategy for CGD: Both patients enrolled in the study had a history of prior CGD-defining complications, including CGD-associated colitis (CAC), and skin and soft tissue infections, and both were maintained on long-term prophylactic therapy.
