Nanobiotix S.A. announced new preclinical immunotherapy data for novel, potentially solid tumor- and therapeutic combination-agnostic radioenhancer NBTXR3 that will be presented at the 2021 Annual Meeting of the Society for the mmunotherapy of Cancer (SITC). The Company believes that these data are consistent with recently presented clinical immunotherapy data and support advancement of development with anti-PD-1 and emerging immune checkpoint inhibitors. Preclinical data to be presented at the meeting by Nanobiotix (Abstract #740) show that radiotherapy-activated NBTXR3 increases CD8+ T cell infiltration and modulates the T cell receptor (?TCR?) repertoire, as well as marked modulation of immunopeptidome in treated tumor cells in a mouse model. Taken together, these variations could indicate that radiotherapy-activated NBTXR3 triggers more robust immune priming than radiotherapy alone and merits further evaluation of CD8+ response and abscopal effect. The Company?s perspective is that these data further support the mechanistic rationale of combining NBTXR3 with immune checkpoint inhibitors. The preclinical data follows preliminary clinical data presented earlier in the fourth quarter of 2021 from the phase I trial ("Study 1100") evaluating NBTXR3 in combination with the anti-PD-1 checkpoint inhibitors nivolumab (Opdivo?) or pembrolizumab (Keytruda?) in patients with locoregional recurrent ("LRR") or recurrent and metastatic ("R/M") head and neck squamous cell carcinoma ("HNSCC") or with lung or liver metastases from any primary cancer that is eligible for anti-PD-1 therapy. This preliminary data for Study 1100 showed an overall AE profile consistent with radiotherapy or anti-PD-1 monotherapies. A 56% target lesion objective response rate (80% in anti-PD-1 na?ve patients; 45% in prior non-responders) was observed in evaluable patients (n=16). A 50% overall objective response rate (% response in target and non-target lesions) was observed (80% in anti-PD-1 na?ve patients; 36% for prior non-responders) in evaluable patients. The potential immune priming effect of radiotherapy-activated NBTXR3 was observed in non-responders as well as anti-PD-1 na?ve patients, suggesting that NBTXR3 may reverse or circumvent resistance to prior anti-PD-1 treatment. Evaluation of novel combination approaches to immunotherapy continues to be a priority for Nanobiotix, as investigators seek to expand the impact of I/O agents for the 80-85% of patients that receive limited benefits, or no benefit at all, by improving response rates and overcoming resistance to anti-PD-1. TIGIT and LAG3, members of the same receptor class as CTLA-4 and PD-1, could be the next generation of immunotherapy targets and are being investigated alone and in combination with existing anti-PD-1 agents aiming to improve patient outcomes in clinical trials. The preclinical data to be presented at SITC by The University of Texas MD Anderson Cancer Center (Abstract #575) show that radiotherapy-activated NBTXR3 plus anti-PD-1, anti-TIGIT, and anti-LAG3 (?Combo therapy?) significantly promotes the proliferation activity of CD8+ T cells, improves local and distant tumor control, and increases survival rate in mice. Only the group of mice treated with the Combo therapy had survivors and those cured mice were immune to re-injection of tumor cells, maintained a significantly higher percentage of memory CD4+ and CD8+ memory T cells, and had stronger anti-tumor immune activities than the control, suggesting the induction of long-term anti-tumor memory by the Combo therapy.