PCSK9 and diabetes mellitus: We present as examples the risks to HVs in studies of 2 classes of non-oncological drugs, namely proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, which lower cholesterol and prevent atherosclerotic cardiovascular disease, and sodium–glucose cotransporter-2 (SGLT-2) inhibitors, which lower serum glucose levels in patients with diabetes and have newly recognized cardiovascular benefits (Table 1).