A Study Evaluating the Safety and Efficacy of JS212 Combination Therapy in Patients With Advanced Esophageal Squamous Cell Carcinoma

An Open-label, Multicenter, Phase II Clinical Study to Evaluate the Safety and Efficacy of JS212 Combination Therapy in Patients With Advanced Esophageal Squamous Cell Carcinoma (ESCC)

This study is an open-label, multi-center phase II clinical trial aimed to evaluat the safety and preliminary efficacy of JS212 combination therapy in patients with advanced esophageal squamous cell carcinoma (ESCC).

Study Overview

• Status: Recruiting
• Conditions: Advanced Esophageal Squamous Cell Carcinoma
• Intervention / Treatment: Drug: JS212; Drug: JS001; Drug: 5-FU

• Study Type: Interventional
• Enrollment (Estimated): 280
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Chengbo Jia; Phone Number: +8618547265054; Email: chengbo_jia@junpharma.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100142
      • Recruiting
      • Cancer Hospital of Chinese Academy of Medical Sciences
      • Contact: Jing Huang, Ph.D; Phone Number: 010-87788102; Email: huangjingwg@163.com
      • Principal Investigator: Jing Huang, Ph.D

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Male or female subjects aged 18 to 75 years (inclusive) at the time of signing the Informed Consent Form (ICF).
2. Histologically or cytologically confirmed esophageal squamous cell carcinoma (ESCC) that is locally advanced, recurrent, or metastatic, and not amenable to radical treatment.
3. No prior systemic anti-tumor therapy. For patients who received neoadjuvant/adjuvant therapy or radical concurrent chemoradiotherapy, the interval from the last dose of chemotherapy to disease recurrence or progression must be > 6 months to be eligible for screening.
4. At least one measurable lesion per Response Evaluation Criteria in Solid Tumors (RECIST 1.1).
5. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
6. Expected survival ≥ 12 weeks

Exclusion Criteria:

1. Prior treatment with any of the following: anti-PD-1 or anti-PD-L1 antibody therapy; ADC therapy targeting EGFR and/or HER3, or ADC therapy with a topoisomerase I inhibitor as the toxic payload;
2. Subjects at high risk of bleeding or esophageal fistula, e.g., lesions with large ulcers or direct invasion of vital adjacent organs such as the aorta or trachea;
3. Subjects with a history of gastrointestinal perforation and/or fistula within 6 months prior to the first dose;
4. Presence of active central nervous system (CNS) metastases;
5. Active autoimmune disease requiring systemic therapy (e.g., corticosteroids or immunosuppressive agents) within 2 years prior to the first dose;
6. Toxicities from prior anti-tumor therapy have not recovered to ≤ Grade 1 per CTCAE v6.0 or to the level specified in the inclusion/exclusion criteria;
7. Severe cardiovascular or cerebrovascular disease;
8. Known hypersensitivity or severe allergic reaction to the study treatment drugs, any of their components, or their excipients；

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort 1:JS212+JS001	Drug: JS212; JS212 will be administered every 3 weeks; Drug: JS001; JS001 will be administered every 3 weeks
Experimental: Cohort 2:JS212+JS001+5-FU	Drug: JS212; JS212 will be administered every 3 weeks; Drug: JS001; JS001 will be administered every 3 weeks; Drug: 5-FU; 5-FU will be administered on d1and d8 every 3 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
dose-limiting toxicity （DLT）	Abnormal changes in laboratory and other tests with clinical significance	up to 4 years
adverse event（AE）	Abnormal changes in laboratory and other tests with clinical significance	up to 4 years
RP3D	Recommended dose for phase III trial	up to 4 years
Objective response rate (ORR) based on Response Evaluation Criteria In Solid Tumors 1.1 (RECIST1.1)	Defined as the proportion of subjects who achieved partial response (PR) or complete response (CR)	up to 4 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression free survival(PFS)	The time from first dose to Disease progression or death	up to 2years
overall survival (OS)	The time from first dose to death from any cause	up to 4 years
immunogenicity	Incidence of Anti-Drug Antibody (ADA)	up to 2years

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biomarker	exploratory analysis of the correlation between potential biomarkers (which may include PD-L1, EGFR, HER3, etc.) and clinical efficacy of JS212 combination therapy.	up to 2years

Collaborators and Investigators

• Sponsor: Shanghai Junshi Bioscience Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): April 13, 2026
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): April 1, 2028

Study Registration Dates

• First Submitted: March 16, 2026
• First Submitted That Met QC Criteria: March 16, 2026
• First Posted (Actual): March 20, 2026

Study Record Updates

• Last Update Posted (Actual): April 22, 2026
• Last Update Submitted That Met QC Criteria: April 21, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Pyrimidines; Uracil; Pyrimidinones; Fluorouracil
• Other Study ID Numbers: JS212-006-II-ESCC

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No