Human Genetics Informing Drug Development in Cardiovascular Disease: Interleukin-6 Signaling as a Case Study

Cardiovascular disease remains the leading cause of death worldwide, calling for the development of novel therapeutics. Over the past 3 decades, substantial investments in human genetic research have unveiled the genetic architecture of cardiovascular disease, offering promising novel therapeutic targets. These discoveries have been instrumental in the development of several cardiovascular drug development programs, such as those targeting proprotein convertase subtilisin/kexin type 9, lipoprotein (a), apo C₃, and angiopoietin-like 3. Large-scale resources such as population-based biobanks and data repositories, now enable human genetic data to be leveraged at scale and inform not only target selection, but also clinical drug development. This review highlights the transformative potential of human genetics in cardiovascular drug development, focusing on IL (interleukin)-6 signaling as a case study. Specifically, we discuss how IL-6 signaling was pinpointed as a key causal mediator of atherosclerosis by genetic data, shaping the current development landscape for anti-IL-6 therapeutics in cardiovascular disease. Recent genetic studies employing innovative methodologies have provided key insights into prioritizing indications for clinical testing, informing repurposing strategies, optimizing clinical trial design for population selection, and assessing safety signals. Despite this progress, methodological challenges, such as pleiotropic effects of genetic variants, extrapolation of small genetic associations to large interventional effects, and the predominance of European-derived data, highlight the need for careful interpretation. Continued methodological advances, coupled with the emergence of high-throughput omics data and detailed cardiovascular phenotyping, promise unprecedented opportunities to refine drug discovery and development.