Proprotein convertase subtilisin/kexin type 9: From genetics to clinical trials

Purpose of review This review describes the pivotal role of genetic insights and technologies in the discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9) and the rapid development of PCSK9 inhibitors - a revolutionary new class of lipid-lowering agents. Recent findings PCSK9 was discovered as a the third gene implicated in familial hypercholesterolemia. Population genetics studies, enabled by technological advances, were instrumental in validating PCSK9 as a therapeutic target. Monoclonal antibodies against PCSK9 were introduced in the clinic after an unprecedently rapid development path, in which clinical trial results confirmed that these drugs robustly lower cholesterol and improve clinical outcomes regardless of disease indication or background therapy. New strategies to PCSK9 inhibition are underway and have delivered promising preliminary results, including inhibition of PCSK9 synthesis by targeting the cellular gene expression machinery and vaccination. The future will tell whether directly targeting the genome through editing techniques will ultimately enable us to virtually eliminate many of the traditional CVD risk factors. Summary The extraordinary PCSK9 narrative highlights the opportunities offered by genetics-driven drug development and holds valuable lessons for future development programs.