Nanobiotix SA presented results of phase 1/2 head and neck cancer trial with its lead product candidate, NBTXR3, at the American Society of Clinical Oncology.
NBTXR3 is a first-in-class radio-enhancer that can be applied to most solid tumors. It is an aqueous suspension of nanoparticles with a special coating designed to penetrate cancer cells and remain within the tumor. The solution is injected directly into the tumor before radiotherapy session.
The trial targeted frail and elderly patients of more than 70 years who have advanced cancer. These patients can only be treated with radiotherapy instead of a combination of radiotherapy and chemotherapy and so have a poorer outcome. The uncontrolled tumor growth in the population significantly decreases their quality of life because basic functions such as swallowing, breathing, speaking and eating are impaired.
The primary endpoints of the trial were safety and feasibility.
Use of NBTXR3 showed excellent safety profile with no adverse effects. The injection was feasible and appropriate as the product remained in the tumor from the first day until the last day of radiotherapy.
The overall response rate, which was evaluated as per response evaluation criteria in solid tumors 1.1, was 91%, and seven out of nine patients had complete response at 10% dose level or more.
The trial showed that all patients treated at higher dose levels of 15% and 22% had an extended response with no loco-regional or distant relapse, with a medium follow up of 12 months.
The study also showed that most of the complete responses occurred between three and 10 months after the end of the treatment, during the follow-up period when patients were not receiving any oncology treatments.
Nanobiotix will include an immunological biomarkers analysis in the study.
The safety profile of the product also opens up opportunities for its combination with different types of treatment.
Nanobiotix is filing a protocol amendment of the trial to include 44 additional patients in an expansion to demonstrate the efficacy of the product.
The French late stage clinical company is opening 12-15 additional sites in Europe to expand the development of this indication and also plans to expand the study in the U.S.