Phase Ib: To observe the safety and tolerability of SI-B001+SI-B003 combination and to determine the recommended dose (RP2D) for Phase II clinical studies in locally advanced or metastatic head and neck squamous cell carcinoma indications. To evaluate the initial efficacy, pharmacokinetic characteristics and immunogenicity of SI-B001+SI-B003 in patients with locally advanced or metastatic head and neck squamous cell carcinoma. Phase II: To evaluate the efficacy of SI-B001+SI-B003 dual-agent chemotherapy in patients with locally advanced or metastatic head and neck squamous cell carcinoma. The safety, tolerability, PK/PD and immunogenicity of SI-B001+SI-B003 combined chemotherapy in patients with locally advanced or metastatic head and neck squamous cell carcinoma were evaluated.
Phase Ib: To observe the safety and tolerability of SI-B001+SI-B003 in combination and to identify RP2D in locally advanced or metastatic head and neck squamous cell carcinoma indications. Initial efficacy, pharmacokinetic characteristics and immunogenicity were evaluated. Phase II: To evaluate the efficacy of SI-B001+SI-B003 two-drug combination chemotherapy. Safety and tolerance, PK/PD, immunogenicity were evaluated.