Head and Neck Squamous Cell Carcinoma (HNSCC) Clinical Trials

• Aged 18-75 (inclusive) years old, male or females;

• Participants with histologically confirmed recurrent or metastatic head and neck squamous cell carcinoma who are not suitable for radical surgery or concurrent chemoradiotherapy.

• For SYS6010 combined with Enlonstobart group: Participants who have not previously received systemic anti-tumor treatment. If participants have received neoadjuvant or adjuvant therapy (or combination targeted therapy), they are eligible if disease progression occurs at least 6 months after the last administration.

• For Enlonstobart group: Participants who have not previously received immunotherapy are included. For participants who have not previously undergone systemic antitumor treatment, baseline PD-L1 positivity (CPS≥1) must be confirmed by the central laboratory; for participants who have previously received systemic antitumor treatment, there is no restriction on baseline PD-L1 expression.

• At least one measurable lesion confirmed by CT or MRI scan according to RECIST v1.1 criteria

• ECOG performance status of 0-1;

• Life expectancy ≥ 3 months;

• Major organ function must meet the criteria within 7 days prior to the first dose of the study intervention

• Women of childbearing potential must have a negative blood pregnancy test within 7 days prior to the first dose. Participants must agree to use effective contraception from the time of signing the informed consent form until 7 months after the last dose; during this period, women should not be breastfeeding, and men should avoid donating sperm;

⁃ Voluntarily participate in this clinical study, understand the study procedures, and be able to sign a written informed consent form.