PDCD1 and ovarian cancer: Although clinical evidence regarding the efficacy of CD24 blockade is currently limited, the compelling preclinical data in various tumor types—including but not limited to those with dismal prognosis and limited efficacy of PD-1/PD-L1 axis inhibition such as in pancreatic and ovarian cancer—as well as the pressing clinical need for novel treatment strategies might provide enough justification for the accelerated clinical testing of CD24 axis inhibitors.