High Capacity poly(2-oxazoline) formulation of TLR 7/8 agonist extends survival in a chemo-insensitive, metastatic model of Lung Adenocarcinoma

Abstract

About 40% of the NSCLC patients have Stage IV cancer at the time of diagnosis. The only viable treatment options for metastatic disease are systemic chemotherapy and immunotherapy. Nonetheless, chemoresistance remains a major cause of chemotherapy failure. New immunotherapeutic modalities such as anti-PD1 checkpoint blockade have shown promise; however, response to such strategies is highly variable across patients. Here, we show that our novel poly(2-oxazoline) (POx) based nanomicellar formulation of Resiquimod, an imidazoquinoline TLR 7/8 agonist, had a superior tumor inhibitory effect in a metastatic model of lung adenocarcinoma, relative to anti-PD1 immune checkpoint blockade therapy as well as platinum-based chemotherapy, which is the mainstay of treatment for NSCLC. Investigation of the in vivo immune status following Resiquimod PM (POx micellar formulation of Resiquimod) treatment showed that Resiquimod-based stimulation of antigen-presenting cells in the tumor microenvironment resulted in the mobilization of anti-tumor CD8+ immune response. Our study demonstrates the promise of optimally delivered and nano-formulated Resiquimod as a new immunomodulating therapeutic strategy for the treatment of metastatic NSCLC.