ADU-S100

Candidates such as ADU-S100 and MSA-2 demonstrate enhanced STING activation and clinical potential...Future directions emphasize the development of smart nanocarriers with spatiotemporal control, biomarker-driven patient stratification, and combinatorial regimens that integrate epigenetic or metabolic modulators. This review underscores the transformative potential of cGAS-STING-targeted therapies while outlining critical hurdles and interdisciplinary strategies to advance precision cancer immunotherapy.

NanoSTING@Mn, composed of ADU-S100 complexed with Mn2⁺ and encapsulated in biomimetic liposomes, potently activates the cGAS-STING pathway, induces a type I interferon response, and promotes lymphocyte infiltration...Upon intravenous rechallenge, disseminated tumor cells are eliminated, preventing metastasis and ensuring long-term protection. This synergistic approach offers a scalable platform to boost immunotherapy efficacy and redefines immune-based metastasis prevention strategies.

In this work, a therapeutic gel scaffold made from Mn2+-cross-linked sodium alginate (Mn(II)-SA-Gel), which contains a stimulator of interferon genes (STING) agonist (ADU-S100) and an immune checkpoint inhibitor (aCTLA-4), was developed as a drug delivery system for cancer therapy...Moreover, Mn2+ promotes the generation of highly cytotoxic hydroxyl free radicals in the presence of H2O2, and in combination with the immune checkpoint inhibitor aCTLA-4, enhances the T-cell immune response to enhance their powerful tumor cell-killing effect. The findings indicated that Mn(II)-SA-Gel could serve as a promising platform to synergistically stimulate the STING pathway, thereby improving cancer immunotherapy.

Incorporating lymphocyte activation gene 3 (LAG3) blockade further strengthens systemic antitumor immunity by suppressing myeloid-derived suppressor cells while augmenting type 2 conventional dendritic cells, cytotoxic T lymphocytes, and tissue-resident memory T cells. Our findings highlight the potential of STBF-PDT-STING agonism-anti-LAG3 combinations for metastatic and locally advanced cSCC.

LASIP is a transformative dissolvable microneedle patch loaded with antiPD-L1 antibodies, liposomal formulation of drugs (ADU-S100) that activate the stimulator of interferon genes (STING) pathway, and liposomal formulation of a biocompatible dye (IR783) that converts near-infrared light to mild hyperthermia (∼43 °C)...We show an "immunometabolic" correlation of these key metabolites to markers of DC maturation, Tregs, STING activation, and cytokines. Our findings demonstrate that by integrating three treatment modalities, LASIP elicits both innate and adaptive immune responses and enables metabolic reprogramming in the tumor microenvironment to enable antitumor immunity.

Current therapeutic strategies prioritize isoform-specific agonists (e.g. cyclic dinucleotides like ADU-S100; non-CDNs like diABZI) and precision delivery systems, such as nanoparticles and engineered bacteria, to address challenges like short half-life and systemic toxicity...However, the pathway's dual roles, particularly its tumor-promoting effects in advanced malignancies, necessitate context-dependent modulation. This review integrates preclinical insights and clinical trial data to outline strategies for harnessing cGAS-STING signaling in cancer immunotherapy while balancing its immunostimulatory and immunosuppressive outputs.

In vivo, treatment with the VPS34 inhibitor SB02024 enhances the positive effects of the STING agonist ADU-S100 in melanoma tumor-bearing mice. Thus, our study suggests that VPS34 inhibitors could be used to enhance STING-based anticancer therapies. CCL5 (C-C motif chemokine 5); CXCL10 (C-X-C motif chemokine 10); IFN (interferon); VPS34 (vacuolar protein sorting 34); cGAS (cyclic GMP-AMP Synthase); STING (stimulator of interferon genes protein); cGAMP (2'3'-cyclic guanosine monophosphate-adenosine monophosphate).

In addition, due to the acid-sensitive property of the polycationic polymer, the delivery system of LNP-B was more biocompatible and safer compared with lipid nanoparticles formulated with an indissociable cationic DOTAP (LNP-D). These findings suggest that LNP-B has great potential in the intravenous delivery of CDNs for tumor immunotherapy.

A pH-responsive amphiphilic diblock copolymer was synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization and conjugated with STING agonist ADU-S100 and mannose to specifically target dendritic cells (DCs)...The combination with anti-PD-1 antibodies further enhanced tumor control, immune cell infiltration, and survival rates compared to monotherapy. The pH-responsive nano-vaccine combined with anti-PD-1 antibodies showed remarkable synergistic effects in BC treatment, highlighting its potential to enhance immune checkpoint blockade therapy and offer a promising strategy for clinical applications in solid tumors.

Our results suggest that STING agonists may be able to work indirectly in MCC via signaling through immune and stromal cells in the TME, and may not necessarily need STING expression in the cancer cells. This approach may be particularly effective in tumors that are already infiltrated by inflammatory cells in the TME but are evading immune detection via HLA-I downregulation.

This study evaluated whether combining a cationic plant-derived nanoparticle adjuvant (Nano-11) with the clinically tested STING agonist ADU-S100 (MIW815) could stimulate anticancer immunity by intradermal vaccination...Therapeutic vaccination with NanoST increased mouse survival by inhibiting B16-OVA tumor growth, and this effect was further enhanced by PD-1 checkpoint blockade. Our study provides a strong rationale for developing NanoST as an adjuvant for intradermal vaccination and next-generation preventative and therapeutic cancer vaccines by STING-targeted activation.

An alternative phosphorothioate (referred to as endo-S-phosphorothioate) whereby the sulfur atom is endo to the cyclic phosphate ring (i.e. 5'-S-phosphorothioester linkage) would not have chirality at phosphorus and hence not pose diastereomer separation problems. Herein, we report the design and synthesis of novel 5'-endo-phosphorothioate substituted 2'3'cGAMP analogues that are hydrolytically stable towards both ectonucleotide phosphodiesterase I (ENPP1, a mammalian phosphodiesterase) and poxvirus immune nucleases (poxin, a phosphodiesterase in Poxvirus) but retains STING-TBK1-IRF activation, comparable to clinical candidate, ADU-S100 in THP1 monocytes.