Adaptive Adjuvant Therapy After Neoadjuvant Therapy and Gastrectomy for Gastric or Gastroesophageal Junction Adenocarcinoma

NCT07603349 | Not Yet Recruiting Phase 2

• 1 other identifier: NFEC-2026-306
• Study Type: interventional
• Target: 405
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate postoperative adaptive adjuvant therapy in patients with gastric or gastroesophageal junction adenocarcinoma after neoadjuvant chemotherapy plus immunotherapy and radical gastrectomy.The main questions it aims to answer are:

1. 1.In patients with poor pathological response, does switching to a alternative postoperative treatment regimen improve survival?
2. 2.In patients with complete pathological response, can observation without routine postoperative treatment maintain favorable survival outcomes? Participants will be assigned to different cohorts according to their pathological response after surgery and will be followed regularly for recurrence, survival, and treatment-related side effects.

Conditions

Gastric Adenocarcinoma; Gastroesophageal Junction Adenocarcinoma

Keywords

Gastric cancer; Gastroesophageal junction cancer; Neoadjuvant therapy; Adaptive adjuvant therapy; Pathological response; Prognosis

Outcome Measures

Primary Outcomes (2)

• Median Event-Free Survival in Cohort 1（mEFS）

  defined as the time from randomization to the first documented local, regional, or distant recurrence, or death from any cause, whichever occurs first.

  Up to approximately 13 months

• 2-year Event-Free Survival Rate in Cohort 2（2-y EFS）

  defined as the proportion of participants in Cohort 2 who are alive without documented local, regional, or distant recurrence at 2 years after cohort assignment.

  Up to 2 years

Secondary Outcomes (7)

• 1-year Event-Free Survival Rate in Cohort 1（1-y EFS）

  Up to 1 year

• 1-Year Overall Survival Rate in Cohort 1（1-y OS）

  Up to 1 year

• Median Overall Survival in Cohort 1（mOS）

  Up to approximately 3 years

• 2-Year Overall Survival Rate in Cohort 2（2-y OS）

  Up to 2 years

• 3-year Event-Free Survival Rate in Cohort 2（3-y EFS）

  Up to 3 years

Study Arms (3)

Cohort 1 Experimental Arm

EXPERIMENTAL

Participants randomized to the cohort 1 experimental arm will switch to an alternative postoperative treatment regimen. The alternative regimen will be selected by the investigator based on the participant's preoperative treatment regimen, postoperative molecular subtype, and the 2025 CSCO and 2025 NCCN guidelines. The regimen should include taxane-based or irinotecan-based monotherapy or combination therapy that was not used before surgery. The administration schedule and dosage of adjuvant therapy will follow standard clinical practice guidelines and the relevant drug prescribing information.

Drug: Alternative Postoperative Treatment Regimen

Cohort 1 Control Arm

ACTIVE COMPARATOR

Participants randomized to the Cohort 1 control arm will continue treatment according to the preoperative treatment regimen. The administration schedule and dosage of adjuvant therapy will follow standard clinical practice guidelines and the relevant drug prescribing information.

Drug: Original Treatment Regimen

Cohort 2

EXPERIMENTAL

Participants in Cohort 2 will undergo postoperative observation without routine antitumor drug therapy. They will receive regular follow-up monitoring according to the study protocol.

Other: Postoperative Observation

Interventions

Alternative Postoperative Treatment Regimen DRUG

Participants in this arm will switch to an alternative postoperative treatment regimen selected by the investigator according to prior neoadjuvant therapy, postoperative molecular subtype, and the 2025 CSCO and NCCN guidelines. The regimen will include taxane-based or irinotecan-based treatment that was not used before surgery, with dosage and administration based on clinical practice standards and drug prescribing information.

Cohort 1 Experimental Arm

Original Treatment Regimen DRUG

The original preoperative treatment regimen will be continued postoperatively. The administration schedule and dosage of adjuvant therapy will follow standard clinical practice guidelines and the relevant drug prescribing information.

Cohort 1 Control Arm

Postoperative Observation OTHER

Participants will undergo postoperative observation without further antitumor drug therapy. Routine follow-up monitoring will be conducted according to the study protocol.

Cohort 2

Eligibility Criteria

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

You may qualify if:

• Voluntarily signed written informed consent.
• Aged 18 to 75 years, inclusive, regardless of sex.
• Underwent radical gastrectomy with D2 or more extended lymphadenectomy and achieved R0 resection. Surgical approaches may include open or laparoscopic surgery.
• Histopathologically confirmed gastric or gastroesophageal junction adenocarcinoma.
• Received preoperative neoadjuvant immunotherapy combined with chemotherapy, including oxaliplatin plus fluoropyrimidine-based chemotherapy. Immunotherapy may include anti-PD-1 monoclonal antibodies, anti-PD-L1 monoclonal antibodies, PD-1/CTLA-4 bispecific antibodies, and other immune checkpoint inhibitors.
• Eligible for one of the following predefined cohorts:
• Cohort 1: TRG grade 3 and postoperative pathological stage ypT3-4N2-3M0.
• Cohort 2: TRG grade 0 and postoperative pathological stage ypT0N0M0.
• ECOG performance status of 0 or 1.
• No evidence of metastasis or recurrence on postoperative imaging before enrollment.
• Adequate organ function, defined as hematologic, hepatic, renal, and thyroid function meeting the protocol-specified criteria based on laboratory tests performed within 14 days before randomization.
• Willing and able to comply with the study treatment, scheduled visits, laboratory tests, and other study procedures.
• Female participants of childbearing potential must have a negative pregnancy test before enrollment and agree to use effective contraception during the study and for 6 months after the last dose of study treatment. Male participants with female partners of childbearing potential must agree to use effective contraception during the study and for 6 months after the last dose of study treatment.

You may not qualify if:

• Presence of liver, peritoneal, or other distant metastases.
• Inability to take oral medications.
• Unresolved postoperative complications at the time of randomization, such as postoperative infection, anastomotic leakage or wound dehiscence, gastrointestinal bleeding, pancreatic fistula, or intestinal obstruction.
• Uncontrolled pericardial effusion, uncontrolled pleural effusion, or clinically significant moderate or greater ascites at screening, defined as any of the following: pleural effusion or ascites with clinical symptoms and detectable by physical examination; or pleural effusion or ascites requiring drainage and/or intracavitary treatment during screening.
• Underwent any surgery requiring general anesthesia that was not related to gastric cancer within 28 days before randomization.
• History of or current diagnosis of another malignancy within 5 years.
• Active or prior autoimmune disease that may relapse or require immunosuppressive treatment within 2 weeks or during the study period; or a history of immunodeficiency, including HIV positivity or other acquired or congenital immunodeficiency disease; or a history of organ transplantation.
• Participation in another clinical study, or any condition that may interfere with the interpretation of the study results.
• Any other severe acute or chronic disease that, in the investigator's judgment, may increase the risk associated with study participation or study treatment.
• Active or uncontrolled infection requiring systemic antibiotic therapy within 2 weeks before randomization or at the time of randomization.
• Diagnosis of interstitial pneumonia, noninfectious pneumonitis, pulmonary fibrosis, or acute lung disease.
• Active tuberculosis within 1 year or previous anti-tuberculosis treatment.
• Female participants who are pregnant, breastfeeding, or planning to become pregnant during treatment or within 6 months after the end of treatment.
• History of psychotropic drug abuse with inability to discontinue, or presence of a psychiatric disorder.
• Patients considered unsuitable for participation in this study by the investigator.

Sponsors & Collaborators

• Nanfang Hospital, Southern Medical University: lead

Study Sites (1)

Nanfang Hospital, Southern Medical University

Guangzhou, Guangdong, China

Location

MeSH Terms

Conditions

Stomach Neoplasms

Condition Hierarchy (Ancestors)

Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Stomach Diseases

Central Study Contacts

Liying Zhao, M.D., Ph.D

CONTACT

13430396746; zlyblue11@163.com

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: May 18, 2026
• First Posted: May 22, 2026
• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): August 1, 2029
• Study Completion (Estimated): December 1, 2029
• Last Updated: May 22, 2026

Record last verified: 2026-05

Locations

CN (1)