Continuation of Serplulimab Plus Chemotherapy After First Progression in Advanced Gastric or Gastro-oesophageal Junction Adenocarcinoma: an Open-label, Randomised Phase II Trial

Study Overview
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Brief Summary
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This study is conducted in patients with advanced metastatic gastric cancer including gastroesophageal junction cancer(patients with HER2 negative and PD-L1 CPS≥5).Patiens will recevie Serplulimab plus chemotherapy ((oxaliplatin+capecitabine) as first-line treatment. After PD，patients will randomly 2：1 assigned to treatment：one group will receive Serpluimab with Paclitaxel,Apatinib；another group will receive Paclitaxel with or without Ramucirumab.All of eligible patients will receive study drug treatment until loss of clinical benefit, unacceptable toxicity, death, withdrawal of informed consent

Detailed Description
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stage one ：Serplulimab 3mg/kg,d1,q2w or 4.5mg/kg,d1,q3w+oxaliplatin130mg/m2 iv.gtt d1+capecitabine 1000mg/m2 p.o.b.i.d d1 d14,q3w stage two:Serplulimab 3mg/kg,d1,q2w or 4.5mg/kg,d1,q3w+Apatinib 250mg/qd+Paclitaxel 135 175mg/m2 iv.gtt,d1,q3w Paclitaxel 135 175mg/m2 iv.gtt,d1,q3w±Ramucirumab 8mg/kg,d1,q2w

Official Title
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SCAFIGC：Continuation of Serplulimab Plus Chemotherapy After First Progression in Advanced Gastric or Gastro-oesophageal Junction Adenocarcinoma: an Open-label, Randomised Phase II Trial

Conditions
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Gastric Cancer (GC) Gastroesophageal Junction Cancer (GEJ)

Intervention / Treatment
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* Drug: Serplulimab+Paclitaxel+Apatinib
* Drug: Paclitaxel±Ramucirumab


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Volunteer to participate in this clinical study; completely understand and know this study as well as sign the informed consent form (ICF); be willing to follow and be able to complete all study procedures; Age ≥ 18 years and ≤ 75 years when ICF is signed; Unresectable locally advanced, or metastatic gastric cancer including gastroesophageal junction cancer, and histopathologically confirmed diagnosis of adenocarcinoma; never received systemic anti-tumor drug therapy before； HER2 negative and PD-L1 CPS≥5; Measurable lesion according to RECIST v1.1 by IRRC; ECOG score 0-1; Exclusion Criteria: Has other active malignancies within 5 years before the first administration of the study drug; Plan to or have previously received organ or bone marrow transplantation; Uncontrollable pleural effusion, pericardial effusion or ascites requiring repeated drainage; Have received any research drugs within 14 days before the first use of the study drugs.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: Serplulimab
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: continuation of Serplulimab plus chemotherapy after first progression<br>Serplulimab+Paclitaxel+Apatinib Paclitaxel±Ramucirumab | Drug: Serplulimab+Paclitaxel+Apatinib<br>* Immunotherapy+chemotherapy<br>* Other names: A:Drug:Serplulimab+paclitaxel+Apatinib;Drug: Paclitaxel±Ramucirumab<br>* chemotherapy±Targeted therapy<br>* Other names: B:Drug:paclitaxel±Ramucirumab;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 6-month PFS% | Progression-free survival by IRRC assessment per RECIST 1.1 | The Percent of patinets after first progression until disease progression in 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| OS | Overall survival | From the date of first dose unitl the date of death from any cause，assessed up to 2 years ] | 
| PFS2 | Progression-free survival by IRRC assessment per RECIST 1.1 | From date of randomization until the date of second-line treatment progression or date of death from any cause, whichever came first | 
| PFS1 | Progression-free survival by IRRC assessment per RECIST 1.1 | From date of randomization until the date of first documented progressionor date of death from any cause, whichever came first |