Phase 2 RiMO-301 hafnium-based MOF radiosensitizer + pembrolizumab (PD-1) with neoadjuvant RT in HNC.

This Phase 2 neoadjuvant study at the University of Illinois Chicago tests whether adding intratumoral RiMO-301—a hafnium-based nanoscale metal–organic framework (MOF) radio-enhancer that increases local radiation energy deposition and reactive oxygen species generation to intensify tumor kill—can raise major pathologic response when paired with hypofractionated radiotherapy and pembrolizumab, Merck & Co.’s PD-1–blocking antibody that restores antitumor T-cell activity. Participants have resectable, locally advanced head and neck cancer and receive a single intratumoral RiMO-301 injection, then 5 fractions of 4–5 Gy over ~1–2 weeks, plus pembrolizumab 200 mg every 3 weeks for 2 cycles, followed by surgical resection. The key commercial/scientific angle is a “local–systemic” strategy: a tumor-injected, high‑Z radio-enhancer intended to deepen local response while checkpoint blockade may help convert radiation-induced antigen release into systemic immune control. For resectable, locally advanced head and neck cancer today’s care is surgery with risk-adapted adjuvant radiation or chemoradiation, or definitive concurrent chemoradiation (often cisplatin-based) in organ-preservation approaches; this trial explores a short-course pre-op intensification to improve pathologic response and early survival endpoints.