A systematic review of gene editing clinical trials

Gene editing technologies such as zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN), and clustered regularly interspaced short palindromic repeats (CRISPR) have revolutionized genetic engineering and now are being used in clinical gene therapy. We systematically reviewed gene editing clinical trials from ClinicalTrials.gov using a searching strategy that included all different gene editing technologies, followed by two rounds of independent assessment based on the inclusion and exclusion criteria, data extraction, and review of the background publications. 76 trials met our inclusion criteria including 30 studies on genetically engineered T-cell therapies for cancer, 19 studies on virus infections, and 26 studies on monogenic diseases. We have also analyzed the proportions to which different gene editing and gene delivery methods are used. We observed a growing trend of registered CRISPR-based trials indicating a raising interest in developing new therapeutic methods based on this technology. Overall, our study showed that there are promising phase-I and -II trials testing the safety and feasibility of gene editing in different clinical settings.