• Sign informed consent form prior to the commencement of any research activity/procedure.

• Age ≥ 18.

• Cohort 3 (mCRPC cohort) is male-only, and no gender restrictions for other cohorts.

• Subjects with advanced solid tumors who meet one of the following requirements can be enrolled in the study. No cohorts planned for the Phase Ib study, whereas the Phase II study is divided into 6 cohorts:

‣ Cohort: 1 Histologically or cytologically confirmed recurrent or metastatic head and neck squamous cell carcinoma (including nasopharyngeal carcinoma),has progressed after treatment with a standard regimen containing PD-1/PD-L1 inhibitors.

⁃ Cohort 2: Histologically confirmed advanced urothelial carcinoma (including urothelial carcinoma of bladder, renal pelvis, ureter, and urethral origin) that is not suitable for surgical treatment and has progressed after treatment with a standard regimen containing PD-1/PD-L1 inhibitors.

⁃ Cohort 3:

⁃ Metastatic castration-resistant prostate adenocarcinoma with histological or cytological evidence of disease progression except neuroendocrine or small cell carcinoma; Imaging examination (CT/MRI/ bone scan) confirmed metastatic lesions.

• Failed previous standard treatments, and at least received one second-generation anti-androgen drug treatment (including but not limited to abiraterone acetate, enzalutamide or apalutamide).

• Disease progression at screening.

• Continuous luteinizing hormone-releasing agonist (LHRHa) or antagonist therapy (drug castration) or prior bilateral orchiectomy (surgical castration).

• Testosterone at screening was at castration level.

⁃ Cohort 4: Subjects with histologically or cytologically confirmed extensive-stage small cell lung cancer with disease progression after first-line standard therapy.

⁃ Cohort 5: Subjects with histologically or cytologically confirmed locally advanced or metastatic non-small cell lung cancer.

⁃ Cohort 5a: Previous use of and resistant to EGFR inhibitors and failed standard treatment.

• Cohort 5b: No driver gene mutations identified and failed standard therapy containing PD-1/PD-L1 inhibitors.

⁃ Cohort 6: Subjects with advanced solid tumors other than those described in the above cohorts, and failed standard therapy. For recurrent or metastatic cervical cancer, it should be histologically or cytologically confirmed as squamous cell carcinoma, progressed after systematic standard treatment, and is not suitable for radical therapy .

• For patients who have progressed on treatment with PD-1/PD-L1 inhibitors administered either as monotherapy, or in combination with other checkpoint inhibitors or other therapies, PD-1/PD-L1 inhibitor treatment progression is defined by meeting all of the following criteria:

∙ Has received at least 2 doses of approved PD-1/PD-L1 inhibitors.

‣ Documented objective radiographic progression following initiation of treatment with a PD-1/PD-L1 inhibitor. Subjects should not be enrolled if they are suspected of permanent withdrawal due to pseudo-progression after previous PD-1/PD-L1 inhibitor treatment.

• To the extent possible, provide formalin-fixed, paraffin-embedded (FFPE) tumor tissue section (previously archived or fresh) samples and blood samples that meet the detection requirements for exploratory studies.

• Life expectancy ≥ 3 months.

• At least one measurable lesion according to RECIST 1.1 criteria.

• Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1.

• Have adequate organ function.

• Females of child-bearing potential and males who use adequate birth control through 6 months post last dose.