A Phase 3, Global, Multi-Center, Double-Blind, Randomized, Efficacy Study of Zolbetuximab (IMAB362) Plus mFOLFOX6 Compared With Placebo Plus mFOLFOX6 as First-line Treatment of Subjects With Claudin (CLDN)18.2-Positive, HER2-Negative, Locally Advanced Unresectable or Metastatic Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma
The goal of the study is to find out if zolbetuximab with mFOLFOX6 helps patients to live longer by stopping the cancer from getting worse.
- Experimental: Arm A (Zolbetuximab, mFOLFOX6)
- Placebo Comparator: Arm B (Placebo plus mFOLFOX6)
- Subject has histologically confirmed diagnosis of Gastric or GEJ adenocarcinoma.
- Subject has radiologically confirmed locally advanced unresectable or metastatic disease within 28 days prior to the first dose of study treatment.
- Subject has measurable disease according to RECIST 1.1 within 28 days prior to the first dose of study treatment. For subjects with only 1 measurable lesion and prior radiotherapy, the lesion must be outside the field of prior radiotherapy or must have documented progression following radiation therapy.
- Subject's tumor expresses CLDN18.2 in ≥ 75% of tumor cells demonstrating moderate to strong membranous staining as determined by central immunohistochemistry (IHC) testing.
- Subject has a HER2-Negative tumor as determined by local or central testing on a gastric or GEJ tumor specimen.
- Subject has ECOG performance status 0 to 1.
- Subject must meet all of the following criteria based on the centrally analyzed laboratory tests within 14 days prior to the first dose of study treatment. In case of multiple laboratory data within this period, the most recent data should be used to determine eligibility.
- Hemoglobin (Hgb) ≥ 9 g/dL. NOTE: Subject must not have received any growth factor or blood transfusions within 14 days prior to the hematology values obtained at screening. Subjects requiring transfusions to meet eligibility criteria are not eligible.
- Absolute neutrophil count (ANC) ≥ 1.5 x 10^9/L
- Platelets ≥ 100 x 10^9/L
- Albumin ≥ 2.5 g/dL
- Total bilirubin < 1.5 x upper limit of normal (ULN)
- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x ULN without liver metastases (or ≤ 5 x ULN if liver metastases are present)
- Estimated creatinine clearance ≥ 30 mL/min
- Prothrombin time (PT)/international normalized ratio (INR) and partial thromboplastin time (PTT) ≤ 1.5 x ULN (except for subjects receiving anticoagulation therapy)