This is a multicenter, open-label, Phase Ib/II study conducted in China to evaluate the safety, efficacy, and pharmacokinetic (PK) characteristics of YL201 combined with Toripalimab (doublet regimen) or YL201 combined with Toripalimab and Cisplatin (triplet regimen) in subjects with recurrent or metastatic nasopharyngeal carcinoma.

Inclusion Criteria:

1. Voluntarily sign a written informed consent form (ICF).

2. Aged ≥18 years and ≤75 years, male or female.

3. ECOG performance status score of 0 or 1.

4. Life expectancy ≥ 3 months.

5. Disease and treatment history:

   1. Histologically or cytologically confirmed recurrent or metastatic nasopharyngeal carcinoma that is not amenable to curative treatment.
   2. Patients with newly diagnosed advanced nasopharyngeal carcinoma, categorized as Stage IV according to the 9th Edition of the American Joint Committee on Cancer (AJCC) Staging System; or those with recurrent nasopharyngeal carcinoma deemed unsuitable for local treatment
   3. Metastatic or recurrent patients who are systemic treatment naïve.

6. At least one measurable lesion according to RECIST v1.1.

7. Adequate organ function.

Exclusion Criteria:

1. History of other malignant tumors within 5 years prior to the first dose of study drug. Subjects who have been cured of other tumors by local therapy, such as basal cell carcinoma, squamous cell carcinoma of skin, bladder cancer in situ, cervical carcinoma in situ, or breast cancer in situ, are not excluded.
2. Patients with brainstem metastases, leptomeningeal metastases, spinal cord metastases, or spinal cord compression.
3. Patients with severe, uncontrolled cardiovascular disease.
4. Patients with concomitant pulmonary disease resulting in clinically severe impairment of respiratory function.
5. History of interstitial lung disease (ILD) or non-infectious pneumonitis requiring corticosteroid therapy, OR current ILD or non-infectious pneumonitis.
6. Prior treatment with a B7-H3 targeted therapy (including antibodies, antibody-drug conjugates [ADCs], CAR-T cells, and other agents), or with a topoisomerase I inhibitor or an ADC containing a topoisomerase I inhibitor payload.
7. Prior treatment with a PD-(L)1 inhibitor (including antibodies, antibody-drug conjugates [ADCs], CAR-T cells, and other agents).