CD274 and head and neck squamous cell carcinoma: The RNA-lipoplex (RNA-LIP)-based mRNA vaccine BNT113, encoding HPV-16 E6 and E7 (administered intravenously) combined with pembrolizumab, is evaluated in a recruiting randomized phase II trial enrolling patients with HPV 16-positive and PD-L1 expressing R/M HNSCC as first-line therapy.