A study of neoadjuvant-adjuvant durvalumab and FLOT chemotherapy followed by adjuvant durvalumab in Chinese patients with resectable GC/GEJC.

Inclusion Criteria

• Inclusion Criteria:
• - 1. Capable of giving signed informed consent.
• 2. Male and/or Female, Age ≥ 18 years at the time of screening.
• 3. Histologically documented gastric or gastroesophageal junction adenocarcinoma with resectable disease, GEJC includes Siewert* type 2 and 3 tumour and Siewert* type 1 tumour.
• (a) Per the judgment of the Investigator, participants must be medically fit for treatment with neoadjuvant FLOT therapy prior to radical surgery.
• (b) At screening, complete surgical resection of the primary GC/GEJC must be deemed achievable, as assessed by a multidisciplinary evaluation, which must include a board certified GI surgeon.
• (c) No prior anti-cancer therapy (eg, chemotherapy, radiation therapy, or chemoradiation therapy) for the current malignancy.
• 4. ECOG PS of 0 or 1 with no deterioration over the previous 2 weeks prior to baseline at screening and prior to randomization.
• 5. Adequate organ and marrow function as defined below:
• (a) Haemoglobin ≥ 9.0 g/dL
• (b) Absolute neutrophil count ≥ 1.5 × 109/L
• (c) Platelet count ≥ 100 × 109/L
• (d) Serum bilirubin ≤ 1.5 ×ULN. This will not apply to participants with confirmed Gilbert’s syndrome, who will be allowed in consultation with their physician.
• (e) ALT and AST ≤ 2.5 × ULN
• (f) Measured CL > 50 mL/min or Calculated CL > 50 mL/min as determined by Cockcroft-Gault (using actual body weight)
• 6. Must have a life expectancy of at least 24 weeks.
• 7. Body weight > 30 kg at enrolment and randomization.
• 8. Meeting tumour sample requirements (at screening) to confirm PD-L1 status.
• Exclusion Criteria:
• - -1. Participants with peritoneal dissemination (including tumour cells in peritoneal fluid) or distant metastasis.
• 2. Participants with adenosquamous cell carcinoma, squamous cell carcinoma, or GI stromal tumour.
• 3. History of allogeneic organ transplantation.
• 4. Active or prior documented autoimmune or inflammatory disorders (including inflammatory bowel disease [eg, colitis or Crohn’s disease], systemic lupus erythematosus, sarcoidosis, granulomatosis with polyangiitis, Graves’ disease, rheumatoid arthritis, hypophysitis, uveitis, etc), autoimmune pneumonitis, and autoimmune myocarditis.
• 5. Uncontrolled intercurrent illness that would limit compliance with study requirement, substantially increase risk of incurring AEs or compromise the ability of the patient to give written informed consent.
• 6. History of another primary malignancy except for
• (a) Malignancy treated with curative intent and with no known active disease ≥ 2 years before the first dose of study intervention and of low potential risk for recurrence
• (b) Adequately treated non-melanoma skin cancer or lentigo maligna without evidence of disease
• (c) Adequately treated carcinoma in situ without evidence of disease
• 7. History of active primary immunodeficiency.
• 8. Active infection including tuberculosis (clinical evaluation that includes clinical history, physical examination and radiographic findings, and tuberculosis testing in line with local practice) and HIV verified by positive HIV-1 or HIV-2 antibodies.
• 9. Mean QTc ≥ 470 ms calculated from 3 ECGs (within 15 minutes at 5 minutes apart).
• 10. Known allergy or hypersensitivity to any of the study interventions or any of the study intervention excipients.