Phase 2 Study: OBI-833/OBI-821 Maintenance for Globo H+ Advanced Biliary Tract Cancer After Gemcitabine/Cisplatin

Prior treatment

• Treatment with any of the following therapies within 4 weeks prior to the first dose of OBI-833/OBI-821:
  • Anti-cancer therapies, including chemotherapy and targeted therapy (except the GemCis regimen).
  • Radiotherapy.
  • Immunotherapy, including monoclonal antibodies, cytokines, interferons, and checkpoint inhibitors.
  • Immunosuppressants, including cyclosporin, rapamycin, tacrolimus, rituximab, alemtuzumab, natalizumab, and cyclophosphamide.
  • Other biologics, including G-CSF and other hematopoietic growth factors.
  • Live attenuated vaccines.
  • IV/oral steroids except single prophylactic use in CT/MRI scan or other one-time use in approved indications. Use of inhaled and topical (except on the injection site) steroids is allowed.
  • Alternative and complementary medicine that may affect the immune system.
  • Other investigational drugs.

Other illness

• Patient with HIV infection, active hepatitis B infection, or active hepatitis C infection. Patients with hepatitis B infection under anti-HBV medications are exceptionalcan be included in the study. Patients with hepatitis C infection history but inactive status are exceptionalcan be included in the study.
• Patient with any autoimmune or other disorders requiring IV/oral steroids or immunosuppressive or immunomodulatory therapies.
  • (e.g., type 1 juvenile onset diabetes mellitus, antibody positive for rheumatoid arthritis, Graves disease, Hashimoto thyroiditis, lupus, scleroderma, systemic vasculitis, hemolytic anemia, immune mediated thrombocytopenia, Crohn disease, ulcerative colitis, and psoriasis).
• A history of other malignancies (except non-melanoma skin carcinoma, carcinoma in situ of the uterine cervix, follicular or papillary thyroid cancer) within 5 years.
• Patient with any known uncontrolled comorbid illness including ongoing or active infections, symptomatic congestive heart failure (NYHA\>2), unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• Patient with any known severe allergies (e.g., anaphylaxis) to any active or inactive ingredients in the study drugs.

Lab values

• Unresolved toxicities from prior anticancer therapy, defined as having not resolved to Grade 0 or 1 (using National Cancer Institute Common Terminology Criteria for Adverse Events \[NCI CTCAE\] version 5.0), except for alopecia and laboratory values listed in the inclusion criteria.

Other

• Patient who has CNS metastasis or spinal cord compression.
• Patient who is pregnant or breast-feeding at entry.
• Patient with splenectomy.
• Any other reason that the investigator deems the patient to be unsuitable for the study.

• Aged ≥ 20 years.
• Histologically confirmed, unresectable advanced or metastatic biliary tract cancer, including cholangiocarcinoma (intrahepatic or extrahepatic) and gallbladder carcinoma.
• Patient with previously untreated disease if unresectable or metastatic at initial diagnosis will be eligible.
• Patient with recurrent disease \>6 months after curative surgery or \>6 months after the completion of adjuvant therapy (chemotherapy and/or radiation) will be eligible.
• Patient must have a documented Globo H H-score of at least 80 using a validated central IHC assay.
• Patient must have received 3±1 months of the first-line GemCis regimen (gemcitabine, 1000 mg/m2 and cisplatin, 25 mg/m2 on days 1 and 8 of each 21-day cycle), have achieved SD, PR, or CR before enrollment (as confirmed by the Investigator), and plan to continue the GemCis regimen.
• At least one measurable tumor lesion according to RECIST version 1.1 as assessed by the Investigator (local radiological image assessment).
• Life expectancy ≥ 6 months.
• East Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Organ function requirements - Subjects must have adequate organ functions as defined below:
  • AST/ALT ≤ 3X ULN (upper limit of normal); AST/ALT ≤ 5X ULN in the presence of liver metastases Total bilirubin ≤ 2.0 X ULN Serum creatinine ≤ 1.5X ULN ANC ≥ 1,5500 /µL Platelets ≥ 100,000/µL
• All eligible patients of childbearing potential must use effective contraception during study treatment, and for at least 2 months after the last dose of OBI-833/OBI-821. Subjects not of childbearing potential (i.e., permanently sterilized, postmenopausal) can be included in the study. Postmenopausal is defined as 12 months with no menses without an alternative medical cause.
• Understand and provide a written informed consent document according to institutional guidelines.