A Precision Engineered Interleukin-2 for Bolstering CD8+ T- and NK-cell Activity without Eosinophilia and Vascular Leak Syndrome in Nonhuman Primates

SAR-444245 (SAR'245, pegenzileukin) is an extended half-life IL-2 that targets effector CD8+ T and NK cells, with little effect on regulatory T cells. We show that in the nonhuman primate model that closely approximates human immune function and response to IL-2, SAR'245 selectively activates CD8+ T and NK effectors without significant serious side effects (vascular leak syndrome or cytokine release syndrome), suggesting its potential for the treatment of solid tumors in humans.