Clinical Study of Regorafenib and Nivolumab Plus Chemotherapy

Inclusion Criteria

• •1. Histologically confirmed gastric/ gastroesophageal junction/esophageal adenocarcinoma that is confirmed to be unresectable/recurrent disease
• •2. At least 1 measurable lesion as defined by RECIST guideline version 1.1.
• •3. Age \>= 20 years on the day informed consent is obtained
• •4. ECOG Performance status (PS) 0 or 1
• •5. The most recent laboratory value within 14 days prior to enrollment meets all of the following. (Examinations on the same day of the week 2 weeks prior to the day of enrollment may be utilized.) 1)Neutrophils \>= 1,200/mm\^3 2)Hemoglobin \>= 8.0 g/dL 3)Platelets \>= 75,000/mm\^3 4)Total bilirubin \<= 1.5 mg/dL 5)AST (GOT) \<= 100 IU/L If liver metastases are present: \<= 200 IU/L 6)ALT (GPT) \<= 100 IU/L If liver metastases are present: \<= 200 IU/L 7)Creatinine \<= 1.5 mg/dL 8)Urine protein: any of the following (if any of the test criteria are met, other tests may not be performed.) (i)Urine protein (dipstick) \<= 2+ (ii)Urine protein creatinine (UPC) ratio \< 3.5 (iii)Urine protein \<= 3,500 mg for 24-hour collection sample 9)PT-INR: \<= 1.5 (\<= 3.0 if on an anticoagulant)
• •6. No transfusions within 7 days prior to enrollment. (Transfusions on the same day of the week prior to enrollment are allowed)
• •7. Women of childbearing potential must have a negative pregnancy test within 7 days prior to enrollment. Both men and women must agree to use adequate contraception from the time of signing the informed consent form for a period of time (9 months in women and 7 months in men) after the last dose of protocol therapy
• •8. Oral administration is feasible
• •9. Written informed consent to participate in the study has been obtained from the patient themselves
• •10. Confirmed HIV infection
• •11. Patients with concurrent autoimmune disease or a history of chronic or recurrent autoimmune disease. Patients with type 1 diabetes mellitus, hypothyroidism which is manageable by hormone replacement, or skin disorders not requiring systemic treatment (such as vitiligo, psoriasis, or alopecia) are permitted to be enrolled.
• •12. Patients who require treatment with systemic corticosteroids (excluding temporary use for testing or prophylactic administration for allergic reactions, or for reduction of edema associated with radiotherapy), or immunosuppressants, or those treated with any of these therapies within 2 weeks prior to study enrollment
• •13. Patients who fail to use adequate contraception during the study participation and contraception period
• •14. Those unwilling or unable to comply with the protocol
• •15. Those considered by the principal investigator or sub-investigator as ineligible for this investigator-initiated trial