Towards Translation of MU-CN29: New Therapeutic Nanoparticle for Drug-Resistant NSCLC - ABSTRACT Non-small cell lung cancer (NSCLC) is the leading cause of cancer mortality in both men and women. Despite rapid therapeutic advances, the 5-year survival rate of EGFR-mutant NSCLC remains a dismal 16% for the past several decades. In particular, the rapid emergence of resistance to widely used treatments, such as the tyrosine kinase inhibitor (TKI), is the key obstacle to achieving long-term NSCLC patient survival. Further, patients with EGFR mutated tumors fail to respond to immune checkpoint inhibitors (ICIs), leaving them with little to no hope of a long-term remission. Therefore, identifying the molecular determinants of resistance and developing a therapeutic that targets the chemo- and immune-resistant pathways, is the best chance to improve survival rates in NSCLC patients with an EGFR mutation. We hypothesize that MU-CN29, the lead targeted siRNA nanoconjugate, restores sensitivity to tyrosine kinase inhibitors in resistant NSCLC. We further postulate that MU-CN29 will induce a systemic immune response, priming the tumor microenvironment for immunotherapy via ICIs. Therefore, the central objective of this TTNCI proposal is to develop, evaluate, and validate MU-CN29 as an effective therapeutic agent for resistant NSCLC. Our promising in vitro and in vivo experimental results confirmed the crosstalk between the resistance-driving receptor tyrosine kinase AXL and FN14 pathways in drug resistant NSCLC. Additionally, we found that the co-knockdown of both AXL and FN14, using MU-CN29, covalently attached with the dual siRNAs, sensitized the resistant tumors to tyrosine kinase inhibitor (TKI), in vitro and in vivo. To enable translation of MU-CN29 to human trials, in this proposal, we will manufacture the nanoparticles as per FDA guidelines, perform detailed toxicology studies in murine and canine subjects, and evaluate the therapeutic efficacy in clinically relevant animal models. The specific aims of this applications are: (1) Determine MU-CN29 clinical-grade production protocols; (2) Determine the safety and efficacy of MU-CN29 in murine NSCLC models; (3) Establish safety of MU-CN29 in canine cancer patients. The data will validate MU-CN29 nanoparticle platform as a promising strategy to combat drug resistance in NSCLC and catalyze clinical trials in the future.