In vitro activity: Nimorazole,a nitroimidazole anti-infective, is a hypoxic radiosensitizer potentially useful in the treatment of patients with head and neck squamous cell carcinoma (HNSCC). Nimorazole significantly improves the effect of radiotherapeutic management of supraglottic and pharynx tumors and can be given without major side-effects. Nimorazole is the only such chemical reagent that has shown a significant effect in a randomized controlled trial in head and neck cancer.