A Study on the Efficacy of Sodium Propionate Combined With Anti-PD-1 Immunotherapy in Gastric Cancer

Eligible patients with unresectable gastric cancer were randomly assigned to either the sodium propionate group or the control group. In the control group, patients received placebo combined with anti-PD-1 therapy and chemotherapy, without additional sodium propionate intervention. In the sodium propionate group, on the basis of anti-PD-1 therapy combined with chemotherapy, patients were additionally given oral sodium propionate capsules at a dose of 500 mg per capsule, one capsule twice a week, for a total intervention period of 12 weeks. Relevant primary and secondary outcome measures will be collected for further analysis.

• Sodium propionate (Dietary supplement), also known as Propionic acid: on the basis of anti-PD-1 therapy combined with chemotherapy, patients were additionally given oral sodium propionate capsules at a dose of 500 mg per capsule, one capsule twice a week, for a total intervention period of 12 weeks.

Primary outcomes

• Response to treatment for gastric cancer [up to 12 weeks]: Tumor responses in patients with gastric cancer after corresponding treatment were evaluated in accordance with the Response Evaluation Criteria in Solid Tumors (RECIST 1.1).

Secondary outcomes

• Tumor markers [up to 12 weeks]: Serum levels of CEA in ng/mL, CA19-9 in U/mL, CA72-4 in U/mL, AFP in ng/mL and CA125 in U/mL were routinely measured in patients on a monthly basis.
• Patient survival [From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 12 months.]: Follow up on the survival status of patients

Sex: All, ages: 18 Years to 80 Years

Inclusion Criteria:

* Subjects voluntarily participated in the trial and signed the informed consent form;
* Aged ≥ 18 years and < 80 years, regardless of gender;
* Stable vital signs;
* Patients with gastric adenocarcinoma confirmed by gastroscopic biopsy;
* Tumors judged as unresectable by attending physicians;
* Receiving anti-PD-1 therapy combined with chemotherapy as first-line treatment;
* No history of allergic diseases and non-allergic constitution;
* No history of drug abuse;
* Non-pregnant and non-lactating females (applicable to male subjects as well);
* No participation in any drug clinical trial (including investigational drugs of this trial) within 3 months prior to enrollment.

Exclusion Criteria:

* Failure to meet the inclusion criteria, or individuals deemed inappropriate for trial participation by investigators;
* Concurrent primary malignant tumors at other sites;
* Poor general condition, severe infection, respiratory insufficiency, or other conditions leading to inability to cooperate with the trial;
* Patients with mental disorders, consciousness disturbance, or poor treatment compliance;
* Suspected or confirmed history of drug abuse;
* Immunodeficiency, or long-term use of immunosuppressants and glucocorticoids;
* Pregnant or lactating women;
* Sponsors, investigators directly involved in this trial, and their immediate family members;
* Individuals unsuitable for enrollment for any reason as judged by the investigator.

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