Examination of the potential clinical application of 5DEX-0509R, the tumor macrophage-targeting nanomedicine.

Toll-like receptors (TLRs) are crucial for the detection of infections and activation of downstream signaling pathways that lead to the production of pro-inflammatory cytokines and interferons. Because of their strong immunostimulatory activity, TLRs are thought to be a "double-edged sword" for systemic treatment, even in the cancer field. To solve this, we have developed dextran-based TAM targeting activator conjugate (D-TAC) technology which successfully uses tumor-associated macrophages (TAMs) to deliver the TLR7 agonist DSP-0509. We have demonstrated that the anti-tumor effect of our best drug candidate 5DEX-0509R is dependent on the abundance of TAMs, which is consistent with their mechanism of action. In this study, we compared the anti-tumor effects of EIK1001 and 5DEX-0509R, and analyzed its unique immune reaction against tumors to evaluate whether 5DEX-0509R is suitable for further clinical study. 5DEX-0509R showed superior anti-tumor activity compared to EIK1001, an R848 sulfate currently in phase 2 trials, with comparable systemic cytokine profiles. 5DEX-0509R elicited unique CD4 T cell and B cell-dependent anti-tumor effects. We also found that 5DEX-0509R synergistically suppresses tumors with oxaliplatin by changing M2 macrophages that cause oxaliplatin to become resistant to antitumor M1 macrophages. In addition, 5DEX-0509R caused a rapid but not sustained cytokine elevation in both rats and dogs. We believe 5DEX-0509R is worth pursuing for clinical trials.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier Ltd.)