Endothelial lipase (EL) hydrolyzes phospholipids in high-density lipoprotein (HDL) resulting in reduction in plasma HDL levels. Studies with murine transgenic, KO, or loss-of-function variants strongly suggest that inhibition of EL will lead to sustained plasma high-density lipoprotein cholesterol (HDL-C) increase and, potentially, a reduced cardiovascular disease (CVD) risk. Herein, we describe the discovery of a series of oxadiazole ketones, which upon optimization, led to the identification of compound 12. Compound 12 was evaluated in a mouse pharmacodynamics (PD) model and demonstrated a 56% increase in plasma HDL-C. In a mouse reverse cholesterol transport study, compound 12 stimulated cholesterol efflux by 53% demonstrating HDL-C functionality.