Used primarily as a pharmacological tool in research to selectively antagonize the C5a receptor (C5aR), also known as CD88. It is employed in studies involving inflammatory processes, immune cell signaling, and complement system activation. Researchers use it to investigate the role of C5a in diseases such as sepsis, arthritis, asthma, and ischemia-reperfusion injury. Due to its ability to block C5a-mediated effects, it helps in understanding leukocyte migration, cytokine production, and mast cell involvement in inflammation. Commonly applied in in vitro assays and animal models to dissect pathways related to innate immunity and inflammatory disease mechanisms.