Another ongoing phase Ib clinical trial (NCT03906526) is evaluating the effect of the combination of nivolumab (anti-PD-1 inhibitor) and the TLR8 agonist motolimod (VTX-2337) on the immune response as measured by CD3+CD8+ T cell count before and after surgery in subjects with resectable HNSCC [48]. Here, PDCD1 is linked to head and neck squamous cell carcinoma.