Recent Advances in Dual COX/LOX Inhibitor Design (2020–2024): Establishing “The Rule of Four for Inflammation”

The arachidonic acid pathway plays a pivotal role in the biosynthesis of important inflammatory and signal transducing agents such as prostaglandins, leukotrienes and thromboxanes. When this pathway is deregulated, it leads to pathological conditions such as cardiovascular diseases, metabolic diseases, and cancer. Two key enzymes of the pathway are cyclooxygenases (COXs) and lipoxygenases (LOXs), which are responsible for the production of prostaglandins and leukotrienes, respectively. Consequently, these enzymes have long been recognized as key therapeutic targets for the treatment and management of inflammatory disorders and other pathological conditions associated with inflammation. In this review, we describe the new evidence over the last 4 years regarding the arachidonic acid pathway. Moreover, we will pay attention to the structure and function of the COX-2 and 5-LOX enzymes and their role in inflammation, as well as define their active sites. Later, we will discuss the most potent, dual inhibitors of COX-2 and 5-LOX enzymes, based on in vitro and in vivo experiments, from 2020–2024. Structure–activity relationship (SAR) analysis of these compounds revealed four key structural features required for potent dual inhibition of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX). We refer to these criteria as “The Rule of Four for Inflammation”.