Phase 1 MR-guided SBRT (adaptive MR-guided radiotherapy) single-fraction metastasis ablation

This single-arm Phase 1 study (“ONE SHOT”) evaluates feasibility, safety/tolerability, and early local control signals for single-fraction adaptive MR-guided stereotactic body radiation therapy (SBRT) in patients with metastatic solid tumors (excluding central nervous system targets). The intervention is MR-guided SBRT, a high-dose, highly conformal external-beam radiation approach; the “MOA” is direct DNA damage from ionizing radiation, with MR guidance enabling tighter margins, real-time visualization, and on-table adaptive replanning to better spare nearby organs. Imaging and follow-up include MRI and CT at baseline and CT or PET/CT over time to track treated-lesion response and toxicity. The sponsor is the Jonsson Comprehensive Cancer Center (UCLA); the scientific angle is compressing a typically 3–5 fraction SBRT course into one visit while still adapting to daily anatomy using MR guidance. For many patients with limited metastatic sites, today’s care is systemic therapy tailored to the primary cancer (targeted therapy/immunotherapy/chemo) plus local approaches like surgery, thermal ablation, or multi-fraction SBRT for selected lesions—this study tests whether one-day MR-guided SBRT can expand safe, convenient metastasis-directed therapy.