SKB315 in Combination Therapy in Patients With Advanced or Metastatic GC/ GEJ Adenocarcinoma (SKB315)

A Phase II Study Evaluating the Efficacy and Safety of SKB315 Combination Therapy in Claudin18.2 Positive Patients With Unresectable Locally Advanced or Metastatic Gastric or Gastroesophageal Junction Adenocarcinoma

This study is a multicenter,open-label,randomized, phase II clinical study conducted in China. The purpose of this study is to evaluate the efficacy of SKB315 plus PD-1 inhibitor ±capecitabine in patients with Unresectable Locally Advanced or Metastatic Gastric or Gastroesophageal Junction Adenocarcinoma

Study Overview

• Status: Not yet recruiting
• Conditions: Gastroesophageal Junction Adenocarcinoma
• Intervention / Treatment: Drug: Tislelizumab; Drug: SKB315 for injection; Drug: Capecitabine

Detailed Description

This study is a multicenter,open-label,randomized, phase II clinical study conducted in China. The purpose of this study is to evaluate the efficacy of SKB315 plus PD-1 inhibitor ±capecitabine in patients with Unresectable Locally Advanced or Metastatic Gastric or Gastroesophageal Junction Adenocarcinoma

This study will also evaluate efficacy, physical function, safety, and tolerability of SKB315 combination, as well as Pharmacokinetics (PK) of SKB315 and the immunogenicity profile of SKB315 will be evaluated as well.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Yi Ba Professor; Phone Number: 010-69158370; Email: bayi@tjmuch.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China
      • Peking Union Medical College Hospital, Chinese Academy of Medical Sciences
      • Contact: Yi Ba Professor; Phone Number: 010-69158370; Email: bayi@tjmuch.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Locally advanced unresectable or metastatic gastric cancer (GC) or gastroesophageal junction (GEJ) carcinoma and have histologically confirmed adenocarcinoma
2. No previous systemic therapy for locally advanced unresectable or metastatic gastric/GEJ cancer.
3. Consent to provide archival or fresh tumor tissue slides for immunohistochemistry (IHC) assessment, and advanced solid tumors with Claudin 18.2 and PD-L1 expression as determined by IHC;
4. Presence of at least one measurable lesion based on Response Evaluation Criteria in Solid Tumors (RECIST) v1.1;
5. Eastern Cooperative Oncology Group (ECOG) score of 0 or 1;
6. Estimated survival ≥ 3 months as judged by the investigator;
7. Adequate organ and bone marrow function (no blood components and cytokines are allowed within 2 weeks prior to the first dose) ;
8. Patients of childbearing potential (male or female) must use effective medical contraception during the study and for 6 months after the end of dosing;

Exclusion Criteria:

1. Active leptomeningeal disease or uncontrolled brain metastasis
2. Diagnosed with gastric or GEJ adenocarcinoma with positive HER2
3. Received other drugs in clinical study, major surgeries, or any other antitumor therapies within 4 weeks prior to the first dose of study treatment;
4. Patients with active hepatitis B or hepatitis C;
5. Patients have significant gastric bleeding
6. The presence of clinically uncontrollable third interspace fluid
7. Have clinically significant systemic diseases that may adversely affect the safety of the study;
8. Patients who may have poor compliance with the clinical study or have other factors based on which the investigator considers that the patients are not appropriate to patients in the study.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SKB315+Tislelizumab	Drug: Tislelizumab; Tislelizumab will be administered as the protocol described; Drug: SKB315 for injection; Tislelizumab will be administered as the protocol described
Experimental: SKB315+Tislelizumab+capecitabine	Drug: Tislelizumab; Tislelizumab will be administered as the protocol described; Drug: SKB315 for injection; Tislelizumab will be administered as the protocol described; Drug: Capecitabine; Capecitabine will be taken orally as the protocol described

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective Response Rate (ORR)	The sum of the number of cases with Complete Response (CR) and Partial Response (PR) in all treated tumor patients (CR + PR) divided by the total number of cases.	up to 2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety and tolerability assessed by adverse events (AEs)	An AE is any untoward medical occurrence in a subject, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product.	Until 90 days after the end of treatment
Duration of Response (DOR)	Time from the start of the first assessment of CR or PR in tumor patients to PD or death due to any reason.	up to 2 years
Progression Free Survival (PFS)	Time from start of treatment to progression of disease (PD) or death, whichever occurs first, in patients with tumors.	up to 2 years
Overall Survival (OS)	Time from start of treatment to death due to any reason.	up to 2 years
Time to Response (TTR)	Time from the start of treatment to the first assessment of CR or PR in tumor patients.	up to 2 years
Disease Control Rate (DCR)	Proportion of patients with best overall response of CR, PR, or SD and without PD or death due to any reason at the time of assessment in tumor patients.	up to 2 years

Collaborators and Investigators

• Sponsor: Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd.
• Investigators: Principal Investigator: Yi Ba, professor, Peking Union Medical College

Study record dates

Study Major Dates

• Study Start (Estimated): June 30, 2026
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2029

Study Registration Dates

• First Submitted: May 20, 2026
• First Submitted That Met QC Criteria: May 20, 2026
• First Posted (Actual): May 27, 2026

Study Record Updates

• Last Update Posted (Actual): May 27, 2026
• Last Update Submitted That Met QC Criteria: May 20, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Therapeutics; Drug Administration Routes; Drug Therapy; Nucleic Acids, Nucleotides, and Nucleosides; Deoxycytidine; Cytidine; Pyrimidine Nucleosides; Pyrimidines; Nucleosides; Uracil; Pyrimidinones; Deoxyribonucleosides; Fluorouracil; Capecitabine; Injections; tislelizumab
• Other Study ID Numbers: SKB315-II-02

Drug and device information, study documents

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