piSTING: A Pocket-Independent Agonist Based on Multivalency-Driven STING Oligomerization.

Area of Science:

• Immunology
• Pharmacology
• Oncology

Background:

• The stimulator of interferon genes (STING) pathway is a key target for innate immunity modulation.
• Existing small-molecule STING agonists face limitations in clinical efficacy due to reliance on the STING pocket.
• Cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) is the endogenous STING ligand.

Purpose of the Study:

• To develop novel STING agonists independent of the STING pocket.
• To evaluate the efficacy of these novel agonists in vaccine adjuvants and cancer therapy.
• To explore the potential of STING agonists in combination with immune checkpoint blockade.

Main Methods:

• Development of pocket-independent STING-activating agonists (piSTINGs) utilizing multivalency-driven oligomerization.
• Assessment of piSTING-adjuvanted vaccine efficacy in eliciting antibody responses and inhibiting tumor growth.
• Evaluation of piSTING-based vaccine combinations with anti-PD-1 (aPD-1) in immunotherapy models.

Main Results:

• Novel piSTINGs were successfully developed, activating STING independently of pocket interactions.
• A piSTING-adjuvanted vaccine demonstrated significant antibody responses and therapeutic tumor inhibition.
• Combination therapy with piSTING-based vaccines and aPD-1 showed enhanced potential in immunotherapy.

Conclusions:

• Pocket-independent STING agonists (piSTINGs) represent a promising therapeutic strategy.
• piSTINGs can significantly enhance vaccine efficacy and immunotherapy outcomes.
• This approach holds potential for accelerating the clinical translation of STING pathway-based therapies.