Disitamab Vedotin Combined With SOX Regimen Versus SOX Alone as Adjuvant Therapy for HER2-Moderate/High Expressing Stage Ⅲ Gastric Cancer: A Prospective, Multicenter, Randomized, Phase Ⅱ Clinical Trial

NCT07474324 | Recruiting Phase 2

• 1 other identifier: RCVDTYPEC174
• Study Type: interventional
• Target: 124
• Locations: 1 country
• Sites: 1

Brief Summary

This is a prospective, multicenter, randomized, phase II clinical trial intended to enroll patients with HER2-moderate/high-expressing, pathologically staged stage III gastric cancer who have undergone D2 or more extensive surgery. The study aims to evaluate the preliminary efficacy and safety of disitamab vedotin combined with the SOX regimen versus SOX alone as post-operative adjuvant therapy.

Conditions

GC/GEJC

Keywords

adjuvant therapy; Gastric Adenocarcinom; RC48; SOX

Outcome Measures

Primary Outcomes (1)

• 3-year-DFS rate

  The 3-year disease-free survival (DFS) rate is defined as the proportion of participants who remain free of any of the following events for at least three years from the date of randomization: tumor recurrence, new primary tumor, or death from any cause. Patients who undergo curative-intent surgery and experience none of these events are considered disease-free.

  3 years

Secondary Outcomes (5)

• Disease-Free Survival (DFS)

  3 years

• 2-year-OS rate

  2 years

• 3-year OS rate

  3 years

• Overall Survival (OS)

  5 years

• Incidence rate of adverse events (AEs)

  3 years

Study Arms (2)

RC48+SOX

EXPERIMENTAL

Patients will first receive 6 to 8 cycles of treatment with RC48 + SOX

Drug: RC48; Drug: SOX Chemotherapy

SOX

ACTIVE COMPARATOR

Patients will receive 6 to 8 cycles of treatment with SOX

Drug: SOX(normal)

Interventions

RC48 DRUG

RC48 2.5mg/kg iv. ,q3w

RC48+SOX

SOX Chemotherapy DRUG

S-1: 40-60 mg/m², oral administration (p.o.), twice daily (b.i.d.), on Days 1 to 14; repeated every 21 days. Oxaliplatin: 100 mg/m², intravenous infusion (i.v.gtt.), on Day 1; repeated every 21 days.

RC48+SOX

SOX(normal) DRUG

S-1: 40 mg/m², oral administration (p.o.), twice daily (b.i.d.), on Days 1 to 14; repeated every 21 days. Oxaliplatin: 130 mg/m², intravenous infusion (i.v.gtt.), on Day 1; repeated every 21 days.

SOX

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged between 18 and 75 years.
• Have undergone radical resection with D2 or wider lymph node dissection and achieved R0 resection status.
• No prior systemic anti-tumor treatment (i.e., neoadjuvant therapy) before surgery.
• Histopathologically confirmed gastric adenocarcinoma.
• Pathological stage III gastric and gastroesophageal junction adenocarcinoma patients (according to the 8th edition of the American Joint Committee on Cancer \[AJCC\] staging system).
• HER2 moderate-to-high expression (IHC 3+ or 2+).
• Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1.
• Expected survival time ≥ 3 months.
• Able to understand the study protocol, voluntarily participate in the study, and provide written informed consent;
• Good compliance and able to cooperate with the treatment regimen specified in this study;
• Possesses complete imaging and pathological clinical data;
• Adequate organ and bone-marrow function.

You may not qualify if:

• Primary stage III gastric or gastroesophageal-junction adenocarcinoma not histologically or cytologically confirmed;
• Unable to receive disitamab vedotin or SOX chemotherapy;
• Unable to comply with the required follow-up schedule;
• Unable to accept the treatment regimen specified in this protocol;
• Unable or unwilling to undergo mandated response assessments (e.g., CT imaging);
• Active autoimmune disease;
• History of psychoactive-substance abuse that cannot be discontinued, or any severe/uncontrolled psychiatric disorder, or any severe/uncontrolled systemic disease;
• Any concomitant condition that, in the investigator's opinion, poses significant risk to the subject or could compromise study completion;
• Other malignancies within 5 years before screening, except adequately treated cancers considered cured (e.g., thyroid cancer, cervical carcinoma in situ, basal/squamous-cell skin cancer, or ductal carcinoma in situ of the breast treated with curative surgery);
• Lactating women;
• Prior neoadjuvant therapy or intra-operative intraperitoneal chemotherapy.

Sponsors & Collaborators

• The First Affiliated Hospital with Nanjing Medical University: lead

Study Sites (1)

The First Affiliated Hospital with Nanjing Medical University

Nanjing, Jiangsu, 210000, China

RECRUITING

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 11, 2026
• First Posted: March 16, 2026
• Study Start: March 15, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2030
• Last Updated: March 16, 2026

Record last verified: 2026-01

Locations

CN (1)