"To overcome the limitations of IL-2 as a therapeutic agent, two strategies have evolved: tumor-targeted rather than systemic delivery and engineered variants of IL-2 that preferentially activate IL-2-mediated signaling through the IL-2Rβγ heterodimeric receptor without concomitantly activating IL-2Rα (CD25) and consequentially amplifying Tregs. Both strategies have been incorporated into PD1-IL2v, a bispecific antibody molecule (dubbed an immunocytokine) that combines CD8+ T cell targeting via PD-1 binding with an IL-2 variant (IL2v) defective in binding to CD25."
https://www.cell.com/immunity/fulltext/S1074-7613(22)00642-2#.Y722Hd52BG0.twitter