Neoadjuvant Tislelizumab + LM-302 + S-1 or Tislelizumab + SOX for CLDN18.2-Positive Gastric/GEJ Adenocarcinoma

NCT07569068 | Recruiting Phase 2 DMC

• 1 other identifier: DRAGON-18
• Study Type: interventional
• Target: 88
• Locations: 1 country
• Sites: 1

Brief Summary

In this study, the investigators will use Tislelizumab combined with LM-302 and S-1 versus Tislelizumab combined with SOX to treat Claudin 18.2-positive locally advanced gastric or gastroesophageal junction adenocarcinoma.

Conditions

Gastric or Esophagogastric Junction Adenocarcinoma

Keywords

Gastric or Esophagogastric Junction Adenocarcinoma; Claudin 18.2; LM-302; Tislelizumab; SOX

Outcome Measures

Primary Outcomes (1)

• Pathological complete response (pCR) rate

  pCR is defined as the absence of residual tumor based on evaluation of the resected stomach and lymph node specimen according to Becker remission criteria

  up to 24 months

Secondary Outcomes (6)

• treatment related adverse events

  up to 24 months

• Major Pathological Response (MPR) rate

  up to 24 months

• R0 resection rate

  up to 24 months

• Event-free survival (EFS)

  up to 36 months

• Overall survival (OS)

  up to 36 months

Study Arms (2)

Tislelizumab Combined With LM-302 and S-1

EXPERIMENTAL

Drug: Tislelizumab, LM-302 and S-1

Tislelizumab Combined With SOX

ACTIVE COMPARATOR

Drug: Tislelizumab combined with oxaliplatin and S-1

Interventions

Tislelizumab, LM-302 and S-1 DRUG

Tislelizumab 200mg and LM-302 2.0mg/kg intravenous (IV) infusion on day 1 plus oral S-1: BSA\<1.25 m2, 40mg twice/day; BSA1.25-1.5m2, 50mg twice/day; BSA≥1.5 m2, 60mg twice/day, po, d1-14, q3w.

Tislelizumab Combined With LM-302 and S-1

Tislelizumab combined with oxaliplatin and S-1 DRUG

Tislelizumab 200mg and oxaliplatin 130 mg/m2 intravenous (IV) infusion on day 1 plus oral S-1: BSA\<1.25 m2, 40mg twice/day; BSA1.25-1.5m2, 50mg twice/day; BSA≥1.5 m2, 60mg twice/day, po, d1-14, q3w.

Tislelizumab Combined With SOX

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients voluntarily participate in this study and sign the informed consent form;
• Age ≥ 18 years;
• Histopathologically confirmed gastric adenocarcinoma or gastroesophageal junction adenocarcinoma;
• HER2 negative;
• Determined by contrast-enhanced CT and laparoscopy to have radically resectable disease with clinical stage T3-4 N+ M0 (according to the AJCC 8th edition);
• Claudin 18.2 positive (≥25% of tumor cells showing moderate-to-strong membrane staining);
• No prior receipt of other targeted therapies against claudin 18.2;
• ECOG performance status 0-1;
• Life expectancy ≥ 12 months;
• Adequate major organ function.

You may not qualify if:

• Known HER2-positive gastric cancer；
• Gastroesophageal junction (EGJ) cancer involving the proximal stomach with the tumor center located ≤2 cm from the EGJ；
• Peritoneal metastasis, positive peritoneal cytology (CY1P0), or retroperitoneal lymph node metastasis (No. 16a2/b1) or other distant metastases;
• Presence of unresectable factors, including unresectability due to tumor characteristics, surgical contraindications, or patient refusal of surgery;
• Prior or concurrent other malignancy, except for cured basal cell carcinoma of the skin, carcinoma in situ of the cervix, and carcinoma in situ of the breast;
• Presence of any of the following cardiac clinical symptoms or diseases:
• New York Heart Association (NYHA) class ≥2 heart failure or left ventricular ejection fraction (LVEF) \<50% on color Doppler echocardiography;
• Unstable angina;
• Resting electrocardiogram (ECG) showing QTc \>450 ms (male) or QTc \>470 ms (female);
• Resting ECG showing clinically significant abnormalities (e.g., abnormalities in heart rate, conduction, morphology), complete left bundle branch block, third-degree atrioventricular block, second-degree atrioventricular block, or PR interval \>250 ms.
• History of gastrointestinal perforation, intra-abdominal abscess, or intestinal obstruction within the past 3 months, or evidence of intestinal obstruction by imaging or clinical symptoms;
• Arterial/venous thrombotic events within 6 months before randomization, such as cerebrovascular accident (including transient ischemic attack, cerebral hemorrhage, cerebral infarction), deep vein thrombosis, or pulmonary embolism;
• Known hereditary or acquired bleeding or thrombotic predisposition (e.g., hemophilia, coagulation disorders, thrombocytopenia);
• Active peptic ulcer, unhealed wound, or bone fracture;
• Active infection requiring antimicrobial therapy (e.g., antibacterial, antiviral, or antifungal treatment);

Sponsors & Collaborators

• Ruijin Hospital: lead

Study Sites (1)

Ruijin Hospital Shanghai Jiao Tong University School of Medicine

Shanghai, Huangpu District, 200025, China

RECRUITING

MeSH Terms

Interventions

tislelizumab; S 1 (combination); Oxaliplatin

Intervention Hierarchy (Ancestors)

Coordination Complexes; Organic Chemicals

Central Study Contacts

Zhongyin Yang

CONTACT

8621-64370045; jeffreyyong@163.com

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Doctor

Study Record Dates

• First Submitted: April 17, 2026
• First Posted: May 6, 2026
• Study Start: April 21, 2026
• Primary Completion (Estimated): April 30, 2028
• Study Completion (Estimated): April 30, 2029
• Last Updated: May 6, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)