MSA-2 dimer, a selective and orally active non-nucleotide STING agonist with a dissociation constant (Kd) of 145 μM, demonstrates prolonged antitumor and immunogenic activity. It non-covalently binds to STING as a dimer, showing greater permeability compared to cyclic dinucleotide[1].

STING:145 μM (Kd)

MSA-2 dimer (60 mg/kg; p.o.; 50 days) inhibits tumor growth and prolongs overall survival[1]. MSA-2 dimer (40 mg/kg; s.c.; 25 days) induces complete tumor regression[1].MSA-2 dimer (60 mg/kg; p.o.; 4 hours) increases proinflammatory cytokine (IFN-β) level in tumors[1].MSA-2 dimer (60 mg/kg; s.c.; 4 hours) concentrations is observed in tumors than in plasma or other nontumor tissues [1].MSA-2 dimer (THP-1 cells) induces phosphorylation of both TBK1 and IR. MSA-2 dimer (10 μM and 33 μM; macrophages) induces IFN-β[1].MSA-2 dimer also exhibits dose-dependent antitumor activity when administered by IT, SC, or PO routes[1].