The drug nimorazole belongs to a class of chemicals known as 5-nitroimidazoles. Drugs from this class are used against infection. In addition, nimorazole makes tumour cells more sensitive to radiotherapy. Therefore, the investigators want to find out whether the addition of nimorazole to the standard treatment with radiotherapy in combination with chemotherapy with cisplatin shows activity against Locally Advanced Head and Neck HPV Negative Squamous Cell Cancers and is safe. Furthermore, the investigators will investigate if a specific examination done with tumour tissue will help to predict whether the treatment will work or not.