Study Evaluating Treatment of Sacituzumab-govitecan for Patients With Metastatic Esophagogastric Adenocarcinoma

All eligible enrolled patients will receive:Sacituzumab-govitecan 10 mg/kg i.v. at day 1 and day 8 of each 21-day cycle (Q3W). Patients will receive the treatment for a maximum of 12 months or until disease progression, unacceptable toxicity or withdrawal of consent, whichever occurs first.The primary objective of the trial is to evaluate the efficacy (primary endpoint: Overall Response Rate ORR, complete response + partial response) of sacituzumab-govitecan for metastatic esophagogastric adenocarcinoma. The secondary objectives are to further characterize the efficacy of sacituzumab-govitecan for metastatic esophagogastric adenocarcinoma and to evaluate safety and tolerability of sacituzumab-govitecan for metastatic esophagogastric adenocarcinoma. Secondary endpoints comprise the assessment of Clinical benefit rate (CBR, complete response + partial response + stable disease), Progression-free survival (PFS), Overall survival (OS), ORR, CBR, PFS and OS in the subgroup of TROP-2 overexpression, toxiticy. In addition, tissue and blood samples will be analyzed to evaluate the TROP-2 expression during treatment with sacituzumab-govitecan for metastatic esophagogastric adenocarcinoma.

56 patients will be enrolled in this trial.

Inclusion criteria

• Patient* has given written informed consent.
• Patient is, in the investigator's judgement, willing and able to comply with the study protocol.
• Patient is ≥ 18 years of age at time of signing the written informed consent.
• Patient has been diagnosed with histologically confirmed metastatic (stage IV) esophagogastric adenocarcinoma.
• Patient has received at least one prior therapy containing platinum compound and a fluoropyrimidine, potentially combined with immunotherapy, in the metastatic setting. Neoadjuvant/adjuvant platinum-fluoropyrimidine treatment is counted as first-line therapy if disease progression occurred within 6 months after completion of treatment.

NOTE: patients with advanced MSI-h/dMMR tumors who have not previously been treated with pembrolizumab, nivolumab or any other PD-1/PD-L1 inhibitor are not permitted for inclusion.

• Patient has an ECOG performance status ≤ 1.
• Patient must have an estimated life expectancy of at least 12 weeks.
• Patient has at least one measurable lesion on radiographic imaging as defined by RECIST v1.1.
• Patient has adequate hematological, hepatic and renal function as indicated by the following parameters:

• Leukocytes ≥ 2,500/μL, platelets ≥ 100,000/μL without transfusion, absolute neutrophil count (ANC) ≥ 1,500/μL without granulocyte colony-stimulating factor support, hemoglobin ≥ 90 g/L (9 g/dL) - Patients may be transfused to meet this criterion.
• Bilirubin ≤ 1.5 x upper limit of normal (ULN), aspartate transaminase and alanine transaminase ≤ 2.5 x ULN (≤ 5 x ULN in case of liver metastases), alkaline phosphatase ≤ 2.5 x ULN (≤ 5 x ULN in case of liver metastases)
• Serum creatinine ≤ 1.5 x ULN, or glomerular filtration rate > 45 mL/min (calculated per institutional standard)
• Serum albumin ≥ 25 g/L (2.5 g/dL)
• For patients not receiving therapeutic anticoagulation: INR or aPTT ≤ 1.5 x ULN; for patients receiving therapeutic anticoagulation: stable anticoagulant regimen
• Patient must be willing to provide liquid biopsy samples for the translational research program.
• Female patients of childbearing potential and male patients with female partners of childbearing potential must agree to remain abstinent (refrain from heterosexual intercourse) or use contraceptive methods that result in a failure rate of <1% per year during the treatment period and for at least 6 months after the last study treatment. Male patients must refrain from donating sperm during this same period. Male patients with a pregnant partner must agree to

Exclusion criteria

• Patient has known hypersensitivity to any component of the Sacituzumab-govitecan formulation as well as a known history of severe allergic, anaphylactic or other hypersensitivity reactions to chimeric or humanized antibodies or fusion protein.
• Patient has received previously topoisomerase 1 inhibitors such as irinotecan, or nal-irinotecan
• Patient has an active second malignancy. Note: patients with a history of malignancy that have been completely treated, with no evidence of active cancer for 3 years prior to enrollment, or patients with surgically cured tumors with low risk of recurrence (e.g., non-melanoma skin cancer, histologically confirmed complete excision of carcinoma in situ, or similar) are allowed to enroll
• Patients with known, untreated and active (not stable within the last 4 weeks or symptomatic) brain metastases and patients with leptomeningeal disease.
• Patient meets any of the following criteria for cardiac disease:

• Myocardial infarction or unstable angina pectoris within 6 months prior to initiation of study treatment
• History of serious ventricular arrhythmia (i.e., ventricular tachycardia or ventricular fibrillation), high-grade atrioventricular bock, or other cardiac arrhythmias requiring antiarrhythmic medications (except for atrial fibrillation that is well controlled with antiarrhythmic medication); history of QT interval prolongation
• New York Heart Associated (NYHA) class III or greater congestive heart failure or left ventricular ejection fraction (LVEF) of < 40% if echocardiography has been performed
• Patient has an active chronic inflammatory bowel disease (ulcerative colitis, Crohn's disease) or gastrointestinal perforation within 6 months prior to initiation of study treatment
• Patient has an active serious infection requiring antibiotic treatment
• Patient has known history of human immune deficiency virus (HIV, or positive HIV antibody, if done at screening) with detectable viral load OR taking medications that may interfere with SN-38 metabolism
• Patient has active hepatitis B or C virus (HBV/HCV). In patients with a history of HBV or HCV, patients with detectable viral loads will be excluded
• Patient participated in another interventional clinical study ≤ 14 days prior to initiation of study treatment or at the same time as this study.
• Patient has taken an investigational drug within 14 days or 5 half-lives (whichever is longer) prior to initiation of study treatment.
• Patient received anticancer biologic agent within 28 days or targeted small molecule, radiation or chemotherapy within 14 days prior to initiation of the study treatment.
• Patient has not recovered from AEs due to previously administered drug (i.e., ≥ grade 2 is concerned as not recovered)

• Patients with any grade of alopecia are an exception to this criterion and will qualify for the study
• If patients received major surgery, they must have recovered adequately from the toxicity and/or complications from the intervention prior to starting study treatment
• Patient has evidence of any other disease, neurologic or metabolic dysfunction, physical examination finding or laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of any of the study medications, puts the patient at higher risk for treatment-related complications or may affect the interpretation of study results.
• Female patients, who are pregnant or breast feeding or planning to become pregnant within and 6 months after the end of treatment. Female patients of childbearing potential must have a negative serum pregnancy test result within 7 days prior to initiation of study treatment.