A Phase I trial of Johnson & Johnson-licensed JNJ-1900 (NBTXR3), a hafnium oxide nanoparticle radioenhancer developed by Nanobiotix S.A. (Euronext: NANO; Nasdaq: NBTX), has produced its complete cohort results in one of the most difficult-to-treat settings in thoracic oncology: inoperable, locoregionally recurrent non-small cell lung cancer (NSCLC) amenable to re-irradiation. The full-cohort data, presented at the International Association for the Study of Lung Cancer (IASLC) 2026 World Conference on Lung Cancer, produced encouraging local control despite re-irradiation doses lower than patients’ prior radiation courses.
The study, sponsored by The University of Texas MD Anderson Cancer Center, enrolled 24 patients across dose-escalation and expansion phases. All 24 completed treatment with no dose-limiting toxicities and no Grade 3 or higher adverse events attributable to JNJ-1900 or the intratumoral injection procedure. Grade 3 radiotherapy-related adverse events occurred in 33% of patients and Grade 5 in 8% (n=2). The recommended Phase II dose was established at 33% of gross tumor volume. At a median follow-up of 12 months, one-year locoregional control was 79%, one-year local progression-free survival (LPFS) was 61% (median 13.6 months), and one-year overall survival (OS) was 70% (median 14.8 months). The study investigators concluded that JNJ-1900 may permit clinically meaningful local control at substantially reduced re-irradiation doses, and called for evaluation in a randomized trial.
JNJ-1900 consists of functionalized hafnium oxide nanoparticles administered as a single intratumoral injection. When activated by radiotherapy, the nanoparticles physically amplify local energy deposition within the tumor, enhancing tumor cell killing while aiming to spare surrounding tissue; the company also proposes that this mechanism triggers an adaptive immune response. Recurrent NSCLC within a previously irradiated field is particularly resistant to standard re-irradiation because surviving tumor cells have already withstood one radiation course, and surrounding normal tissue has limited residual tolerance — a dual constraint that has historically confined re-treatment to palliative intent.