sl-279252

SL-279252 is a bifunctional hexameric recombinant fusion protein designed as an agonist redirected checkpoint (ARC) immunotherapy. It consists of the extracellular domains of human programmed cell death 1 (PD-1) and tumor necrosis factor ligand superfamily member 4 (OX40L), joined via an inert IgG4-derived Fc domain. The molecule simultaneously blocks the inhibitory PD-1/PD-L1 immune checkpoint pathway and activates OX40 signaling to stimulate T-cell responses within the tumor microenvironment. This dual mechanism aims to enhance anti-tumor immunity by both removing inhibitory signals and providing co-stimulatory activation to T cells. Developed for advanced solid tumors and lymphomas, it was evaluated in Phase 1 clinical trials but discontinued after failing to meet efficacy benchmarks in heavily pretreated patient populations[2][3][5][6].

Other names

ARC fusion protein SL-279252