NCT06940921

SBRT-LDRT-Cadonilimab for Advanced Gastric, Colorectal and Ovarian Cancers With Peritoneal Metastases

A Single-arm, Prospective Clinical Study of Low-dose Radiation Therapy (LDRT) Combined With Stereotactic Body Radiation Therapy (SBRT) and Cadonilimab for Advanced Gastric, Colorectal and Ovarian Cancers With Peritoneal Metastases

• Status: Active Not Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 26 (estimated)
• Sponsor: Zhang Tao · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The goal of this clinical trial is to see if high- and low-dose radiotherapy combined with immunotherapy can work in patients with advanced gastric, colorectal, and ovarian cancers with peritoneal metastases, and to learn about the safety of this new combination treatment modality. The main questions they aim to answer are: * Can whole-abdominal low-dose radiotherapy (LDRT) combined with selected-site stereotactic body radiation therapy (SBRT) followed by Cadonilimab control peritoneal lesions and malignant ascites in patients with advanced solid tumors with peritoneal metastases? * Can the novel treatment modality of high- and low-dose radiotherapy combined with immunotherapy produce a survival benefit in patients with advanced gastric, colorectal, and ovarian cancers who have received multiple lines of therapy? * Is the safety profile of this new treatment modality acceptable? Participants will: * Receive stereotactic body radiation therapy (SBRT) to selected sites and low-dose radiotherapy (LDRT) to the whole abdomen, followed by bi-weekly treatment with Cadonilimab until disease progression, death, toxicity intolerance or withdrawal of informed consent. * Receive whole body imaging and laboratory tests every 6-8 weeks to assess the efficacy of tumor treatment.

Detailed description

Several studies have confirmed that the prognosis for advanced solid tumors for which there is no longer a standard of care is extremely poor, with optimal supportive care and an overall survival time of usually 1-5 months, and better treatment options are urgently needed to benefit patients' survival. For advanced solid tumors with peritoneal metastases, the prognosis is even worse. The peritoneal metastatic lesions respond poorly to chemotherapy, targeting, immunotherapy, surgical treatment, and other currently used treatments, and the expected survival time is short, so there is an urgent need to seek more effective treatment modalities. There is a synergistic effect between radiotherapy and immunotherapy, and several studies have explored the combination of radiotherapy and immune checkpoint inhibitors in the treatment of solid tumors, and the results have shown that this combination regimen has a good anti-tumor effect, but the optimal radiotherapy modality and dose of radiotherapy are still in the exploratory stage. At present, some preclinical studies and small sample studies have shown that the combination of high- and low-dose radiotherapy can change the tumor immune microenvironment, reverse the state of immunosuppression, and play a strong anti-tumor effect in combination with immune checkpoint inhibitors. Therefore, the investigators propose to conduct a single-arm, prospective clinical study of whole-abdominal low-dose radiotherapy (LDRT) combined with stereotactic body radiation therapy (SBRT) followed by Cadonilimab for the treatment of advanced gastric, colorectal, and ovarian cancers with peritoneal metastases. The study evaluates the efficacy of this combination therapy modality on peritoneal metastatic lesions, as well as the objective remission rate (ORR), disease control rate (DCR), duration of remission (DoR), progression-free survival (PFS), overall survival (OS), and safety of the patients. Our study aims to further explore the combination treatment options to improve the efficacy and prognosis of backline treatment for advanced tumors, and to provide more evidence for the clinical practice of radiotherapy combined with immunotherapy in advanced gastric, colorectal, and ovarian cancers with peritoneal metastases.

Conditions

• Advanced Gastric Cancer
• Advanced Colorectal Cancer
• Advanced Ovarian Cancer
• Peritoneal Metastasis

Interventions

Type	Name	Description
RADIATION	Low-Dose Radiation(LDRT) + Stereotactic body radiotherapy (SBRT)	Radiation: Stereotactic Body Radiation Therapy (SBRT) * Stereotactic Body Radiation Therapy (SBRT) will be performed first at a total dose of 20-50 Gy, delivered in 3-5 fractions of 6-10 Gy each. And the target area was specifically selected based on the location and size of the patient's tumor. Radiation: low-dose radiotherapy (LDRT) * Whole-abdominal low-dose radiotherapy will be initiated within 10 days of the end of SBRT with a total dose of 7-15 Gy at 0.5-2.0 Gy twice daily. And the target area included all suspicious tumor tissues and potential metastatic foci in the abdominal cavity.
DRUG	Cadonilimab	· Cadonilimab: 6 mg/kg IV, D1, Q2W, until disease progression, death, toxicity intolerance or withdrawal of informed consent

Timeline

• Start date: 2025-03-20
• Primary completion: 2027-11-30
• Completion: 2027-11-30
• First posted: 2025-04-23
• Last updated: 2025-04-27

Locations

1 site across 1 country: China