Scientists at Verve Therapeutics in Boston conducted the inaugural human trial of base editing, using the treatment VERVE-101 to deactivate the PCSK9 gene in the liver. The gene regulates ‘bad’ cholesterol, and the one-time injection resulted in a significant LDL reduction of up to 55%. This milestone suggests a potential transformative approach to treat coronary artery disease. However, safety concerns emerged, with two serious adverse events, including a death. The findings, presented at the American Heart Association meeting, indicate both promise and challenges for this ground-breaking gene-editing technique.