Nanobiotix S.A. announced new clinical data from a Phase 1 study evaluating radiotherapy-activated NBTXR3 for patients with pancreatic ductal adenocarcinoma (PDAC). The study is being conducted as part of an ongoing collaboration between Nanobiotix and The University of Texas MD Anderson Cancer Center (MD Anderson) and results were presented at the American Association for Cancer Research (AACR) 2023 Special Conference on Pancreatic Cancer. PDAC is an indication associated with poor prognosis and an increasing impact on cancer-related mortality worldwide.

For the more than 90% of patients with locally advanced disease that is not eligible for surgery (unresectable), there are few treatment options with curative intent. As such, the 5-year overall survival rate for patients with unresectable PDAC remains less than 5%. These patients present an urgent unmet need for new treatment options that provide effective local control with tolerable safety profiles.

ABSTRACT #B002: Phase 1 Study of Endoscopic Ultrasound-guided NBTXR3 delivery activated by Radiotherapy for Locally Advanced or Borderline Resectable Pancreatic Cancer (LAPC or BRPC) Given the universal, physics-based mechanism of action of potential first-in-class radioenhancer NBTXR3, promising early signs of safety and efficacy across several other tumor indications, and the urgent need for better treatment options to control local disease in patients with pancreatic cancer, MD Anderson and Nanobiotix aligned to evaluate the potential of the radioenhancer in a Phase 1 study. This Phase 1 study was designed with two parts: The dose-finding part with 1 patient at dose level 1 (33% of gross tumor volume) and 9 patients at dose level 2 (42% of gross tumor volume) The expansion part at the recommended phase 2 dose (RP2D) with 12 additional patients. NBTXR3 was administered prior to radiotherapy (RT) via an endoscopic ultrasound (EUS)-guided intratumoral injection.

All patients received low-dose intensity-modulated radiation (IMRT; 45 Gy) in 15 fractions, and were followed up to one year. Importantly, all patients in the study had previously received a 4-month course of chemotherapy and showed no radiographic evidence of metastases at screening. The first patient at dose level 1 and subsequent 14 patients at dose level 2 had no injection complications.

One patient at dose level 2 had 1 dose-limiting toxicity related to RT (Grade 3 elevated liver function). As of the data cutoff, 13 patients were evaluable for efficacy. 11 patients had stable disease (SD), 1 had progressive disease in the injected lesion, and 1 had a pathological complete response after surgery.

Taken together, these results represent a 92.3% local disease control rate (12/13) and a median Overall Survival of 21 months in evaluable patients. Notably, the patient who achieved pathological complete response entered the study with an unresectable tumor.