Y-90 With Durvalumab/Gem/Cis in Intrahepatic Cholangio

Inclusion Criteria: * Ability to comprehend and willingness to sign a written ICF for the study * Male and female participants at least 18 years of age at the time of signing the ICF * Histologically or cytologically confirmed locally advanced unresectable or metastatic intrahepatic cholangiocarcinoma; at least one intrahepatic lesion must be present * Radiographically measurable or evaluable disease by CT or MRI per RECIST v1.1 criteria * ECOG performance status ≤1 * Body weight \>30 kg * Must have a life expectancy of at least 12 weeks * Participants must have adequate marrow function as defined below: * Hemoglobin ≥9.0 g/dL * Absolute neutrophil count (ANC) ≥1.0 × 109 /L * Platelet count ≥75 × 109/L * Participants must have adequate renal function as defined below: * Serum creatinine ≤ 1.5 mg/dL OR * Measured creatinine clearance (CL) \>40 mL/min or Calculated creatinine CL\>40 mL/min by the Cockcroft-Gault formula (Cockcroft and Gault 1976) or by 24-hour urine collection for determination of creatinine clearance * Participants must have adequate hepatic function as defined below: * Bilirubin ≤1.5 x ULN * ALT ≤ 2.5 x ULN unless liver metastases are present, in which case it must be ≤5x ULN * AST ≤ 2.5 x ULN unless liver metastases are present, in which case it must be ≤5x ULN * This will not apply to patients with confirmed Gilbert's syndrome (persistent or recurrent hyperbilirubinemia that is predominantly unconjugated in the absence of hemolysis or hepatic pathology), who will be allowed only in consultation with their physician * No known history of active HBV or HCV infection. * Note: Participants with Hepatitis C who have been clinically cured, defined as persistent absence of Hepatitis C RNA detected by polymerase chain reaction (PCR) test in serum 12 weeks after completing antiviral treatment, are eligible for this study * Note: Participants with a history of Hepatitis B infection that are currently on viral suppressive therapy are eligible for enrollment * Adequate coagulation studies as demonstrated by prothrombin (PT) and partial thromboplastin (PTT) time within normal limits (\</= 1.5 x ULN) in the absence of anticoagulation medication. Participants receiving anticoagulation may be approved by sponsor * Participants with known human immunodeficiency virus (HIV) on effective highly-active antiretroviral therapy (HAART) with undetectable viral load within 6 months are eligible for this trial, so long as the following criteria are met: * HAART does not interact with or have overlapping toxicities with study medication, per discretion of the treating provider * CD4 count is ≥350 cells/uL, viral load is undetectable, and not taking prohibited cytochrome (CYP)-interacting medications * Probable long-term survival with HIV if cancer were not present * Stable on a HAART regimen for ≥4 weeks and willing to adhere to their HAART regimen with minimal overlapping toxicity and drug-drug interactions with the experimental agents in this study * HIV is not multi-drug resistant * Taking medication and/or receiving antiretroviral therapy that does not interact or have overlapping toxicities with the study medication Exclusion Criteria: * Surgically resectable disease at enrollment * Histologically or cytologically confirmed diagnosis of primary hepatocellular carcinoma or mixed adenocarcinoma/hepatocellular carcinoma * Received prior systemic chemotherapy and/or radiotherapy for intrahepatic cholangiocarcinoma. Prior surgical resection and adjuvant chemotherapy or chemoradiotherapy is allowed if more than 6 months have elapsed since last dose of treatment, and if the tumor is amenable to Y-90 SIRT * Prior treatment with anti-PD-1, anti-PD-L, including durvalumab antibody, or any other drug treatment specifically targeting T-cell co-stimulation or checkpoint pathways * Any of the following within 6 months of screening: * New York Heart Association (NYHA) Class III or IV heart failure * Myocardial infarction, unstable angina pectoris, or symptomatic coronary artery disease * Unstable arrhythmia * Stroke to transient ischemic attack * Previous malignancies, except for adequately treated non-melanoma skin cancer, in-situ cancer, or any other cancer from which the subject has been disease-free for at least 3 years * Severe chronic obstructive or other pulmonary disease with chronic baseline hypoxemia due to potential for gemcitabine-induced bronchospasm and/or durvalumab-induced pneumonitis * Major surgery (other than diagnostic) within 4 weeks of study treatment day 1 * Active, uncontrolled or untreated bacterial, viral, or fungal infection that requires systemic therapy * Active, untreated HIV, HBV, or HCV * Subjects who have participated in another investigational drug or device study within 4 weeks prior to study registration. Pregnant women are excluded from this study because cisplatin is a class D agent with the potential for teratogenic or abortifacient effects. Because cisplatin is present in breast milk and there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with cisplatin, breastfeeding should be discontinued prior to entry into the study. Subjects and their sexual partners entered into the study must agree to contraception. The following restrictions apply while the patient is receiving study treatment and for the specified times before and after: * Female patients of child-bearing potential Female patients of childbearing potential who are not abstinent and intend to be sexually active with a non sterilized male partner must use at least 1 highly effective method of contraception (Table 2) from the time of screening throughout the total duration of the drug treatment and the drug washout period (90 days after the last dose of durvalumab monotherapy). Non-sterilised male partners of a female patient of childbearing potential must use male condom plus spermicide thr