Breakthrough in Cancer Immunotherapy: Design of an Oral STING Agonist Achieves Complete Tumor Regression

Researchers at the University of Michigan have made a significant advancement in cancer immunotherapy by designing a potent oral stimulator of interferon genes (STING) agonist, ZSA-215, which achieves complete tumor regression and long-term survival in mice. This breakthrough has the potential to revolutionize the treatment of various types of cancer, including colon cancer.

Key Takeaways:

• The researchers designed potent oral STING agonists through an intramolecular hydrogen bond ring mimicking strategy, which identified lead compound ZSA-215 with potent cellular STING-stimulating activity.
• ZSA-215 enhanced STING signaling through promoting the phosphorylation of STING and interferon regulatory factor 3 (IRF3) and secretion of IFN-β.
• Monotherapy of oral ZSA-215 achieved complete tumor regression and long-term survival of mice in the MC38 colon cancer model, outperforming MSA-2.
• ZSA-215 exhibited excellent metabolic and chemical stability in vitro, high oral drug exposure (AUC = 23835.0 h·ng/mL), and bioavailability ( = 58%).
• The research suggests that ZSA-215 is a potent oral STING agonist warranting further development for cancer immunotherapy.

Statistics:

• AUC (area under the curve) for oral ZSA-215: 23835.0 h·ng/mL
• Bioavailability of ZSA-215: 58%
• Complete tumor regression and long-term survival rate in mice: 100% (MC38 colon cancer model)

Sources:

• "Design of an Oral STING Agonist through Intramolecular Hydrogen Bond Ring Mimicking to Achieve Complete Tumor Regression." Journal of Medicinal Chemistry, 2025.
• NewsRx. (2025, June 13). University of Michigan Reports Findings in Cancer (Design of an Oral STING Agonist through Intramolecular Hydrogen Bond Ring Mimicking to Achieve Complete Tumor Regression). Chemicals & Chemistry, 4971.