Consistent with Ax-101 activity depending on a functional immune system, delayed type hypersensitivity (DTH) testing showed all responders to be DTH+ (5 tumor reduction, 4 SD); 5 anergic (DTH-) patients had SD at best (2 SD, 3 worse). Current Ax-101 clinical development will leverage its beneficial immunostimulatory properties to augment the efficacy of anti-PD1 inhibitors such as pembrolizumab, nivolumab and cemiplimab.