STK-026

STK-026 is a novel engineered human interleukin-12 (IL-12) partial agonist designed for cancer immunotherapy. Unlike wild-type IL-12, which can cause severe systemic toxicities due to broad activation of both innate and adaptive immune cells, STK-026 is specifically tuned to bias immune activation toward antigen-activated T cells—particularly CD8+ T cells—while minimizing stimulation of natural killer (NK) cells and resting T cells. This selectivity is achieved through diminished binding to the IL-12 receptor subunit beta 1 (IL-12Rb1), which is highly upregulated on activated T cells but expressed at lower levels on NK and resting T cells. Preclinical studies in mouse models and cynomolgus macaques demonstrate that STK-026 retains potent anti-tumor efficacy with a significantly improved therapeutic window, avoiding dose-limiting toxicities such as cytokine release syndrome, hepatotoxicity, lymphopenia, and excessive systemic cytokine induction that are characteristic of unmodified IL-12 therapies. The drug has shown excellent tolerability in preclinical GLP toxicology studies[2][3][5][6][7].

Other names

human interleukin-12 Fc fusion proteinhIL-12-FchIL12-FchIL 12-FcIL-12-FcIL12-FcIL 12-Fcengineered IL-12 partial agonist