European Larynx Organ Preservation Study (ELOS) [MK-3475-C44]

ELOS is a prospective, randomized, open-label, controlled, two-armed parallel group, phase II multicentre trial in local advanced stage III, IVA/B head and neck squamous cell carcinoma of the larynx or hypopharynx (LHNSCC) with PD-L1-expression within tumor tissue biopsy, calculated as CPS ≥ 1 curable by total laryngectomy. Induction chemotherapy (IC) with Docetaxel and Cisplatin (TP) followed by radiation will be compared to additional PD-1 inhibition. Patients will be selected after short induction early response evaluation after the first cycle IC (IC-1) aiming on larynx organ-preservation by additional 2 cycles IC followed by radiotherapy (69.6 Gy) for responders achieving endoscopic estimated tumor surface shrinkage (ETSS) ≥ 30%. Nonresponders (ETSS \< 30% or progressing disease) will receive total laryngectomy and selective neck dissection followed by postoperative radiation or chemoradiation according to the recommendation of the clinics multidisciplinary tumor board. However, Patients randomized into the intervention arm starting day 1 will receive 200 mg Pembrolizumab (MK-3475) i.v. in 3-week cycle (q3w) for 17 cycles (12 months). Treatment with pembrolizumab will continue in the experimental arm regardless of ETSS status after IC-1 in both responders and laryngectomized nonresponders, independent from subsequent decision on adjuvant therapy after TL.