msa-2

MSA-2 is an orally available non-nucleotide STING agonist. The non-covalent dimer of MSA-2 binds to STING with nanomolar affinity. It shows anti-tumor activity in syngeneic mouse tumor models, synergizes with anti-PD-1, stimulates tumor secretion of interferon-β, induces tumor regression, and has long-lasting anti-tumor immunity. [3]

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-IN-12 (compound Y2) acts as an inhibitor of STING. It suppresses IFNβ gene expression induced by SR717 with an IC50 of 0.75 μM. Additionally, STING-IN-12 inhibits STING pathway activation induced by the STING agonist SR717 in THP1 cells and by MSA-2 in mice.