NANOBIOTIX Reports New Data for Potential First-in-Class Radioenhancer NBTXR3 in Combination With Anti-PD-1 Showing Local or Distant Tumor Regression in 76.9% of Evaluable Patients Regardless of Prior Anti-PD-1 Exposure

Data to be Presented at the 2021 Annual Meeting of the American Society for Clinical Oncology

• Results show NBTXR3 plus radiotherapy could potentially stimulate immune response and convert anti-PD-1 non-responders into responders
• Objective response was observed in 60% of anti-PD-1 naïve patients and 50% of prior non-responders
• Data suggest abscopal effect in some patients (i.e., reduction in non-injected / non-irradiated lesions)
• To date, the overall adverse event profile for the 16 injected patients has not differed from what is expected with radiotherapy or anti-PD-1 agents (head and neck cancer and non-small cell lung cancer primary tumors)
• New readout could provide promising signals for NBTXR3 as a potential pillar of immunotherapy
• Following ASCO, Nanobiotix will host an investor event on Friday, June 11, 2021 at 8:00 am Eastern Time (14:00 Central European Time), to provide an in-depth review of the immunotherapy data with several key opinion leaders including study investigators (Register here)

Priming Immune Response and Immunotherapy Combination in Advanced Cancers

Abstract #2590: A Phase I Study of NBTXR3 Activated by Radiotherapy for Patients with Advanced Cancers Treated with an Anti-PD-1 Therapy

Background

The Nanobiotix phase I study of NBTXR3 activated by radiotherapy for patients with advanced cancers treated with an anti-PD-1 therapy (Study 1100), is a multicenter, open-label, non-randomized phase I dose escalation with dose expansion study to establish the recommended phase II dose (RP2D) of NBTXR3 plus radiotherapy in combination with anti-PD-1 in three (3) cohorts: (i) inoperable locoregional recurrent or recurrent and metastatic head and neck cancer (R/M head and neck squamous cell carcinoma; R/M HNSCC); (ii) lung metastasis; (iii) liver metastasis. The study is being administered in the United States.

The secondary endpoints are objective response rate (ORR), safety and feasibility, and body kinetic profile.

Updated Results

Safety

NBTXR3 administration by intratumoral injection was feasible and well-tolerated. To date, the overall adverse event (AE) profile has not differed from what is expected with radiotherapy or anti-PD-1 agents. 16 serious AEs were observed, of which four (4) were identified as NBTXR3 or injection related.

Efficacy

As of the data cut-off, 16 patients in the study received NBTXR3 plus radiotherapy and 13 were evaluable for response. Tumor regression was observed in 76.9% (10/13) of evaluable patients, regardless of prior anti-PD-1 exposure. The study reported tumor regression in 80% (4/5) of anti-PD-1 naïve patients and 60% (3/5) had investigator-assessed objective response, including one (1) complete response according to response evaluation criteria outlined in RECIST 1.1. In patients with prior primary or secondary resistance to anti-PD-1, 75% (6/8) had tumor regression and 50% (4/8) had investigator-assessed objective response. These included one (1) complete response and two (2) partial responses by RECIST 1.1, along with one (1) additional investigator-assessed pathological complete response. Some patients in the study showed delayed tumor response and/or abscopal effect, suggesting NBTXR3 may potentially prime an immune response.

Spider Plot – anti-PD-1 Naïve Patients (see table 1)

Spider Plot – anti-PD-1 Refractory Patients (see table 2)

“These updated data support the potential for NBTXR3 plus radiotherapy in combination with anti-PD-1 to yield a sustained immune response in both anti-PD-1 naïve patients and patients that have progressed on prior anti-PD-1 therapy,” concluded Colette Shen, MD, PhD, an assistant professor of radiation oncology at the University of North Carolina Lineberger Comprehensive Cancer Center and Study 1100 presenting investigator at ASCO. “NBTXR3 plus radiotherapy could stimulate immune response, convert anti-PD-1 non-responders into responders, and could be a promising next step for patients who develop immune checkpoint inhibitor resistance.”

Swimmer Plot – anti-PD-1 Refractory Patients Follow-up (see table 3)

Nanobiotix Investor Event

Nanobiotix will host a virtual investor event featuring several key opinion leaders, including study investigators, after the ASCO Annual Meeting on Friday, June 11, 2021 at 8:00 am Eastern Time (14:00 Central European Time). The discussion will focus on the new immunotherapy data from Study 1100. Register here.