ClinicalTrials.gg
Not yet recruitingNCT07784413Updated Aug 25, 2026

A Sequential Trial of Low-Dose Radiotherapy Followed by Concurrent Immunotherapy, Systemic Chemotherapy, and Intraperitoneal Perfusion in Gastric Cancer With Peritoneal Carcinomatosis

A Phase 2 interventional study of low-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel in Gastric Cancer Peritoneal Metastasis (GCPM), sponsored by Zhejiang Cancer Hospital. Not yet recruiting at 1 site in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-25.

Sponsored by Zhejiang Cancer Hospital · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
40
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This study is a prospective, single-center, open-label, exploratory phase II clinical trial aimed at evaluating the safety, tolerability, and preliminary efficacy of low-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel in patients with gastric cancer and peritoneal metastases. A total of 40 patients with gastric adenocarcinoma who have previously undergone first-line therapy are planned for enrollment. Patients will be grouped based on prior exposure to paclitaxel-based chemotherapy to determine whether they will receive systemic treatment with irinotecan combined with serplulimab or albumin-bound paclitaxel combined with serplulimab, along with local intraperitoneal infusion of bevacizumab analog. The study adopts a Simon two-stage design, with 20 patients enrolled in the first stage. If ≥3 patients achieve objective remission, the study will proceed to the second stage, enrolling an additional 20 patients.

Read the detailed description

In China, most gastric cancer patients are diagnosed at an advanced stage. The peritoneum is the most common site of metastasis for gastric cancer, representing a specific mode of metastasis. Based on cytology of abdominal cavity dropout cells and peritoneal implantation formation, it can be classified into CY1P0, CY1P1, and CY0P1 types. Approximately 20% of patients are diagnosed with peritoneal metastasis preoperatively or intraoperatively, and more than 50% of T3 and T4 stage patients develop peritoneal metastasis after radical surgery. Peritoneal metastasis often leads to malignant ascites, intestinal obstruction, cancer pain, and other complications, severely affecting the quality of life of patients. According to epidemiological data, in 2020, the number of gastric cancer patients with peritoneal metastasis in China reached 523,937 cases 3-6 months, and a 5-year survival rate of less than 2% . Effective control of ascites in gastric cancer patients can not only improve their quality of life but also effectively extend their survival time. The survival period for first-line gastric cancer patients with peritoneal metastasis has increased from 3-6 months with traditional chemotherapy to 12-22 months with comprehensive treatment , but the efficacy for second-line gastric cancer patients with peritoneal metastasis remains limited, and more effective treatment regimens are still needed.

Vascular endothelial growth factor (VEGF) plays a central role in angiogenesis and ascites formation in peritoneal metastases. Research evidence shows that intraperitoneal infusion of anti-VEGF drugs, such as bevacizumab, can effectively control ascites and prolong the time to ascites recurrence. When combined with the immune checkpoint inhibitor sintilimab, the ascites control rate can reach 91%, with partial reduction of peritoneal metastases by more than 30% in some patients. Analysis of immune cells in ascites showed that the CD8+/Treg ratio increased threefold after treatment (P\<0.01), and immunohistochemistry results from peritoneal biopsy indicated upregulation of PD-L1 expression in the combination therapy group (combination group vs baseline: +45% vs +10%), suggesting that blocking VEGF can normalize tumor vasculature, reverse the immunosuppressive microenvironment, enhance T-cell infiltration, and exert synergistic effects study, are actively exploring whether combining immunotherapy with VEGFR inhibitors and chemotherapy can improve survival, but further investigation is still needed.

Recent research findings indicate that low-dose radiation therapy (Low-Dose Radiation, LDR, single dose ≤1 Gy) exhibits distinct biological effects compared to conventional radiation therapy (fractionated dose1.8-3 Gy)20.LDR not only does not cause significantDNA double-strand breaks and apoptosis but also remodels the tumor microenvironment by activating various immune-related pathways.

Based on the aforementioned background, this study proposes an innovative combination therapy strategy: low-dose radiotherapy (LDR) followed by immunochemotherapy. The core mechanisms are as follows: (1) Immune initiation effect: LDR acts as an "immune initiator," inducing immunogenic cell death and activating antigen-presenting cells. The peak of immune activation occurs 24-72 hours after LDR, during which administration of the PD-1 inhibitor (serplulimab) can maximize synergistic effects. (2) Vascular normalization window: A peak in vascular normalization is observed 7-14 days after LDR treatment. Combining anti-VEGF drugs (bevacizumab analog) can maintain the vascular normalization state and improve the distribution of chemotherapeutic drugs in metastases to the peritoneum. (3) Overcoming chemotherapy resistance: LDR downregulates the expression of DNA repair genes in tumor cells, enhancing the cytotoxic action of irinotecan and albumin-bound paclitaxel. Preclinical studies show that 0.5 Gy radiotherapy can increase the concentration of paclitaxel in metastases to the peritoneum by 2.8 times.

This study selected low-dose radiotherapy combined with intraperitoneal infusion of bevacizumab. Based on whether first-line chemotherapy regimens included intravenous chemotherapy with albumin-bound paclitaxel, patients were chosen to receive second-line systemic treatment with irinotecan/albumin-bound paclitaxel combined with serplulimab. The study explores the approach of immune rechallenge and low-dose radiotherapy sequential systemic treatment combined with intraperitoneal infusion therapy, aiming to provide new therapeutic strategies and methods for second-line patients with gastric cancer accompanied by peritoneal metastasis.

02

Conditions studied

  • Gastric Cancer Peritoneal Metastasis (GCPM)

Keywords

  • GCPM
  • Serplulimab
  • HLX04
  • Intraperitoneal infusion
03

In context

Neoplasm Metastasis

4,040 studies on the registry are indexed under Neoplasm Metastasis; 886 are open to participants now.

This study's planned enrollment of 40 is below the median of 50 across 3,268 interventional studies indexed under Neoplasm Metastasis.

Browse Neoplasm Metastasis studies →

Lead sponsor

Zhejiang Cancer Hospital is the lead sponsor of 282 studies on the registry; 117 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • 1. Age >18 years on the day of signing the Form; 2. The subject is able to comprehend the procedures and methods of this clinical study, and voluntarily signs the informed consent form after providing full informed consent.

    3. Gastric or gastroesophageal junction adenocarcinoma (-negative) confirmed by histology or cytology.

    4. Imaging confirmed to peritoneum (PCI score ≥10), not suitable for radical excision 5. Failure of platinum-based chemotherapy (due to progression or inability to tolerate).

    6. CT imaging or PET CT suggests metastases to the peritoneum, or ascites cytology is positive.

    7. PS 0-2, expected survival ≥3 months. 8. Organ function meets the following criteria (within 10 days of first receiving the medicinal product).

    1. Hematology: count ≥100×10⁹/L, ≥8g/dL, ≥1.5×10⁹/L, and no blood products, erythropoiesis-stimulating agents, or colony-stimulating factors therapy received within the past 7 days;
    2. Renal function: Serum creatinine is within the normal upper limit range set by the institution;
    3. Liver function: Total ≤ 1.5×UNL; if total bilirubin > 1.5×UNL, then direct bilirubin should be ≤ UNL, (AST) and alanine aminotransferase (ALT) both ≤ 2.5×UNL, albumin > 2.5 mg/dL;
    4. Coagulation function: (INR), prothrombin time (PT), activated partial thromboplastin time (APTT) ≤1.5×UNL; if the subject is undergoing anticoagulation therapy, it should be within the established therapeutic range; 9. Women of childbearing age must have a negative serum pregnancy test within 72 hours prior to the first administration of the investigational medicinal product. If the urine test result is positive or cannot be confirmed as negative, further serum pregnancy testing is required.

      10. Women of childbearing age must agree to use two effective methods of or undergo surgical sterilization, or choose to avoid any heterosexual intercourse throughout the study period and for 120 days after the last drug administration. (Women who have been for more than one year and have not undergone surgical sterilization are considered infertile.) Lactating women must cease breastfeeding.

      11. Male subjects should agree to adopt effective contraceptive measures from the first administration until 120 days after the final administration.

Exclusion criteria

Exclusion Criteria:

  • 1. Presence of active to the central nervous system or meningitis carcinomatosa.

    2. There is an uncontrolled abdominal infection, intestinal obstruction, grade 3 abdominal effusion, or risk of gastrointestinal fistula and perforation.

    3. Study participants received systemic therapy within 28 days prior to treatment.

    4. Known to be allergic to any product or any of the investigational product.

    5. Diagnosed with other within the past 5 years, and the tumor is currently in a progressive stage or requires therapy (excluding basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or cervical carcinoma in situ that has undergone potential radical treatment).

    6. There is active disease, and systemic therapy (including the use of disease-modifying drugs, , or immunosuppressants) has been received in the past two years. Replacement therapy (e.g., thyroxine replacement for hypothyroidism, insulin therapy for diabetes, or physiological glucocorticoid supplementation for adrenal/pituitary insufficiency) is not considered systemic therapy.

    7. Previously suffered from (non-infectious) pneumonia requiring glucocorticoid therapy, or currently suffering from pneumonia.

    8. There is an active infection requiring systemic therapy. 9. The presence of any history of disease, therapy, or laboratory abnormalities that could potentially interfere with the test results, affect the subject's full participation, or be deemed unsuitable for the subject's participation in the study by the Sub investigator.

    10. Past or current presence of mental disease or drug abuse, deemed by the sub investigator as unable to comply with trial requirements.

    11. Already pregnant or in lactation, or plans to become pregnant or cause pregnancy during the trial period (from the start of pre-screening or screening visit to 120 days after the final administration).

    12. Known infection with (HIV1/2 antibody positive).

    13. Known to have (e.g., HBV Hepatitis B Surface Antigen positive) or (e.g., HCV RNA test positive).

    14. Received any within 30 days prior to the first use of the investigational medicinal product.

Terms in these criteria, in plain language(23)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

HER2

HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.

In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

Line of therapy

A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.

“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.

ECOG performance status

A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

INR, PT and aPTT (clotting tests)

Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.

Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Excipients

The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

Autoimmune disease

A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.

Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

Live vaccines

Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
40 participants (estimated)

Study arms

  • Experimental
    Experimental Group

    low-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel group

    Drug: low-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel

Interventions

  • Druglow-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel

    low-dose radiotherapy (LDR) sequentially combined with serplulimab, bevacizumab analog, and irinotecan or albumin-bound paclitaxel

06

What researchers measure

Primary outcomes

  1. PFS

    Progression-free survival

    Time frame: 12 months

Secondary outcomes

  1. ORR

    Objective Response Rate

    Time frame: 12 months

  2. OS

    Overall Survival

    Time frame: 36 months

  3. DOR

    Duration of remission

    Time frame: 36 months

  4. DCR

    Disease Control Rate

    Time frame: 12 months

  5. Safety assessment

    TEAEs

    Time frame: 36 months

07

Study locations

1 site
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Start is estimated for Sep 2026; primary completion for Sep 2028, 24 months later.

Of 354 non-industry phase 2 interventional studies under Neoplasm Metastasis, half reached primary completion within 60 months of starting (the median), counting those still running; a quarter within 36 and three quarters within 90. This study's planned 24 months is below that.

Counting every sponsor, half of 442 studies reached it within 55 months; a quarter within 33 and three quarters within 83.

How these figures are worked out, and which studies are left out of them.

Registered
Aug 21, 2026
First posted
Aug 25, 2026
StartEst.
Sep 1, 2026
Primary completionEst.
Sep 1, 2028
CompletionEst.
Jul 30, 2029
Last update
Aug 25, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Aug 25, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07784413
Responsible party
Ying Jieer (MD, Zhejiang Cancer Hospital) — Principal investigator
First posted
Aug 25, 2026
Start date
Sep 1, 2026 (estimated)
Primary completion
Sep 1, 2028 (estimated)
Completion
Jul 30, 2029 (estimated)
Last update
Aug 25, 2026

Study contacts

Qi Xu, Master
Contact
zjhzxuqi@163.com
+86-15205813046
Qi Xu, Master
study chair · Zhejiang Cancer Hospital

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.

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