STINGINN, LLC — Department of Health and Human Services STTR Phase I: 102

Description

PROJECT SUMMARY Cellular innate immune sensors, such as STING (STIMULATOR OF INTERFERON GENES), have evolved to detect microbial infection of the cell (1-3). STING controls the potent cytosolic DNA-stimulated innate immune pathways and is activated by cyclic dinucleotides (CDNs) such as cyclic di-GMP and cyclic-di-AMP secreted by intracellular bacteria following infection. Alternatively, STING can be activated by cyclic GMP-AMP (cGAMP) generated by a cellular cGAMP synthase cGAS (MB21D1) after association with aberrant cytosolic dsDNA species, which can include microbial DNA or self-DNA leaked from the nucleus (4). Association with CDNs enables STING to activate the production of type I interferon (IFN) and pro-inflammatory cytokines, which facilitate adaptive immunity (3). Aside from being critical for the protection against microbial infection, STING signaling has been shown to be essential for facilitating robust anti-tumor immunity. Regulation of the immune system to stimulate anti-tumor cytotoxic T cell responses is proving to be a powerful approach for the effective treatment of a variety of cancers. For example, STING agonists, based on synthetic CDNs, have been shown to exert potent anti-tumor properties likely by stimulating APCs and are now being evaluated in Phase I trials for the treatment of cancer. However, such CDNs are highly labile and do not exert potent activity when given systemically. This has limited their use/evaluation to intratumoral and oral administration. Here, we describe a new generation of novel small STING agonists that activate STING signaling, that appear superior to existing CDN’s, for evaluation in anti-tumor therapeutic strategies. The compounds have been generated by STINGINN LLC, based in Miami, in collaboration with the University of Miami School of Medicine, FL.