OSU13

OSU13 is a small molecule inhibitor of the mitotic kinase TTK (also known as Monopolar spindle 1 kinase or Mps1). Developed at The Ohio State University, it is designed to induce therapy-induced senescence (TIS) in tumor cells. This senescence state is characterized by the formation of micronuclei and activation of the cGAS-STING pathway, leading to a pro-inflammatory secretome (SASP) and increased MHC-I expression. These changes prime the tumor microenvironment for immunotherapy by recruiting and activating cytotoxic T cells and NK cells. OSU13 has shown efficacy in murine models, particularly when combined with immune checkpoint inhibitors like anti-PD-1, by converting immune-cold tumors into hot tumors.