PULSAR Combined With Immunotherapy for Unresectable Locally Advanced Gastric Cancer

NCT07607119 | Recruiting DMC

• 1 other identifier: PULSAR-GC-1.2
• Study Type: interventional
• Target: 53
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this prospective, single-center, phase II study is to evaluate the clinical efficacy and safety of combining first-line systemic therapy plus immunotherapy with personalized ultrafractionated stereotactic adaptive radiation therapy (PULSAR) in patients with unresectable locally advanced gastric cancer.

Conditions

Gastric Adenocarcinoma; Stomach Neoplasms; Locally Advanced Gastric Cancer; Unresectable Gastric Cancer

Keywords

HER2-negative Stomach Cancer; Microsatellite Stable Gastric Cancer

Outcome Measures

Primary Outcomes (1)

• Progression-Free Survival (PFS) Rate at 12 Months

  Defined as the percentage of patients alive without any evidence of disease progression per RECIST v1.1 at 12 months, calculated from the end date of the 1st PULSAR fraction.

  PFS at 12 months, calculated from the end date of the 1st PULSAR fraction.

Study Arms (1)

Experimental Group (PULSAR + Immunotherapy)

EXPERIMENTAL

Patients with unresectable locally advanced gastric cancer who did not progress after 3 or more cycles of first-line immunotherapy-containing systemic therapy will receive personalized ultrafractionated stereotactic adaptive radiation therapy (PULSAR)

Radiation: PULSAR (Personalized Ultrafractionated Stereotactic Adaptive Radiation Therapy); Radiation: PULSAR

Interventions

PULSAR (Personalized Ultrafractionated Stereotactic Adaptive Radiation Therapy) RADIATION

Dose Schedule: 6 Gy per fraction administered every 3-4 weeks

Experimental Group (PULSAR + Immunotherapy)

PULSAR RADIATION

Administer a single dose of 6 Gy of radiation, up to a total of 3 cycles, at 3-4 week intervals, along with standard systemic therapy.

Experimental Group (PULSAR + Immunotherapy)

Eligibility Criteria

• Age: 19 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 19 or more years. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-2. Histologically confirmed gastric adenocarcinoma. Tumor biomarker status: HER-2 negative, EBV negative, and Microsatellite Stable (MSS).
• Unresectable, locally advanced extent at initial staging (Para-aortic lymph node \[PALN\] and Supraclavicular lymph node \[SCN\] metastases are allowed).
• Has completed 3 or more cycles of first-line systemic therapy combined with immunotherapy without evidence of disease progression.
• Presence of at least one evaluable lesion according to RECIST v1.1 that is deemed safely irradiable by the investigator.
• Voluntary written informed consent provided by the subject.

You may not qualify if:

• Pregnant or lactating women. Presence of brain metastases or leptomeningeal involvement. Prior history of radiation therapy to the intended target site. Severe uncontrolled comorbidities that, in the investigator's opinion, limit study participation or treatment compliance (e.g., uncontrolled infection, heart failure, arrhythmia, psychiatric illness).
• Inability or unwillingness to comply with the study protocol procedures. Any condition deemed inappropriate for study participation by the principal investigator or attending physician.

Sponsors & Collaborators

• Samsung Medical Center: lead

Study Sites (1)

Samsung Medical Center

Seoul, Select Province/State, 06351, South Korea

RECRUITING

MeSH Terms

Conditions

Stomach Neoplasms

Interventions

DEAE-Dextran

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Dextrans; Glucans; Polysaccharides; Carbohydrates

Central Study Contacts

Jeong Il Yu

CONTACT

+82234109598; ro.yuji651@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: May 19, 2026
• First Posted: May 26, 2026
• Study Start: May 15, 2026
• Primary Completion (Estimated): April 30, 2028
• Study Completion (Estimated): April 30, 2030
• Last Updated: May 28, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

KR (1)