A Study to Compare the Efficacy and Safety of LY01015 and Opdivo® Combined Respectively With Chemotherapy in Advanced or Metastatic Esophageal Squamous Cell Carcinoma

Inclusion Criteria:

1. Willing to sign the informed consent form.

2. Male or female aged 18 to 75 years patients.

3. Histopathologically confirmed esophagus squamous cell carcinoma.

4. Diagnosed with advanced or metastatic ESCC per AJCC 8th edition, not be amenable tocurative approaches( such as definitive chemoradiation/surgery), not received priorsystemic anti-cancer therapy for progressive or metastatic disease. Priorneoadjuvant, adjuvant or definitive radiotherapy/chemoradiotherapy/chemotherapy forlocally advanced diseases is permitted if time from the last dose to recurrence> 24weeks.

5. Must have at least one measurable lesion assessed by investigator per RECIST 1.1criteria .

6. ECOG performance status of 0 to 1.

7. Prior to the first dose, the tumor tissue samples must be provided for PD-L1expression analysis, and PD-L1 TPS≥1%.

8. Expected survival ≥6 months.

9. Adequate organ function at screening.

Exclusion Criteria:

1. Presence of symptomatic brain metastasis or spinal compression, or history ofmeningeal metastasis. Patients with asymptomatic brain metastases who have receivedprior treatment are permitted to enroll if the disease is stable, andcorticosteroids have not been required for at least 4 weeks prior to screening.Patients with carcinomatous meningitis are ineligible, regardless of whether thedisease is clinically stable or not.

2. With high risks of bleeding or fistula due to apparent tumor invasion to esophagusor adjacent organs.

3. Known endoscopy-confirmed near-complete obstruction requiring interventional therapyor with risk of perforation post stent implantation in the esophagus or trachea.

4. Unstable disease within 6 months prior to signing informed consent form, includingbut not limited to unstable angina, myocardial infarction, NYHA Class II or highercardiac failure, severe arrhythmia or cerebrovascular accident (including transientischemic attacks) requiring treatment, or any other poorly-controlled systemicdisease, for example, uncontrolled hypertension (systolic pressure ≥160 mmHg ordiastolic pressure≥100 mmHg) despite standard treatment.

5. Received prior treatment with an anti-PD-1, anti-PD-L1, anti-PD-L2, anti-CD137 oranti-CTLA-4 agent or any other antibody or drug specifically targeting T-cellco-stimulation or checkpoint pathways.

6. Prior cumulative exposure dose of cisplatin>300 mg/m2 and time from the last dose ofcisplatin to randomization ≤12 month.

7. Received a live vaccine within 4 weeks prior to the first dose, or be scheduled toreceive a live vaccine during the entire course of the study.

8. Received systemic chemotherapy, targeted therapy, immunosuppressants,immunostimulants, biological agents, Chinese herbal medicines for anti-tumorindications (prescription or medical record required), Chinese patent drug or anyother investigational agents or participated in interventional clinical study within 4 weeks (or five half-lives, whichever is longer) prior to the first dose.

9. Other conditions, as determined by the investigator, for example, severe deep veinthrombosis, arterial embolism, hepatic encephalopathy, Child-Pugh grade B or moresevere cirrhosis, or other acute or chronic disease, mental illnesses or laboratoryabnormalities, which may lead to the following consequences: increase the risksassociated with study participation or study drug administration, or interfere withthe interpretation of study results.