ALX Oncology Holdings Inc. ALX Oncology Holdings Inc is a clinical-stage immuno-oncology company focused on helping patients fight cancer by developing a pipeline of product candidates based on expertise in protein engineering and oncology led by the CD47 blocker, evorpacept, currently in phase 1 and 2 clinical trials. Cancer cells leverage CD47, a cell surface protein, as a don't eat me signal to evade detection by the immune system. It is developing a next-generation checkpoint inhibitor designed to have a high affinity for CD47 and to avoid the limitations caused by hematologic toxicities inherent in other CD47 blocking approaches.