Up to 154 patients will be recruited in the TACTI-003 (Two ACTive Immunotherapies) Phase IIb study which will take place across several countries in Australia, Europe and United States of America in up to 35 experienced clinical sites. It will evaluate the safety and efficacy of eftilagimod alpha in combination with pembrolizumab against pembrolizumab alone in 1st line metastatic or recurrent HNSCC with PD-L1 positive (CPS ≥1) tumors, and determine the efficacy and safety of efti plus pembrolizumab in patients with PD-L1 negative tumors. Subjects in cohort A (CPS ≥1) will be randomized 1:1 to receive either P+E: efti plus pembrolizumab or P only: pembrolizumab alone. Subjects in cohort B (CPS <1) will receive a combination of efti and pembrolizumab P+E. Efti will be administered for up to 24 months using a 30 mg s.c. dosing every 2 or 3 weeks. Pembrolizumab will be administered for up to 24 months using a 400mg i.v. (30 min) dosing every 6 weeks.
Evaluate the safety and efficacy of eftilagimod alpha in combination with pembrolizumab against pembrolizumab alone in 1st line metastatic or recurrent HNSCC with PD-L1 positive (CPS ≥1) tumors, and determine the efficacy and safety of efti plus pembrolizumab in patients with PD-L1 negative tumors.