Eligibility Criteria:
Inclusion Criteria:
* Age ≥ 18 years, male or female.
* Histologically or cytologically confirmed diagnosis of locally advanced or potentially resectable intrahepatic cholangiocarcinoma or gallbladder cancer, defined as T2b-T4 or N1 M0 according to the AJCC 8th edition.
* Expected life expectancy ≥ 12 weeks.
* No prior systemic treatment for biliary tract cancer before the first dose of study medication.
* At least one measurable lesion as defined by RECIST 1.1 criteria.
* ECOG Performance Status of 0 or 1.
* Adequate organ function, without severe dysfunction of the hematologic, cardiac, pulmonary, hepatic, renal, bone marrow, or immune systems.
* Laboratory tests meeting the following requirements: Women of childbearing potential must have a negative pregnancy test (serum or urine) within 14 days before enrollment and voluntarily use adequate contraception during the observation period and for 8 weeks after the last dose of the study drug. For men, they must be surgically sterile or agree to use adequate contraception during the observation period and for 8 weeks after the last dose of the study drug.
* Patient voluntarily participates and provides written informed consent.
* Good compliance is anticipated, allowing for efficacy and adverse event follow-up per the protocol.
Exclusion Criteria:
* The subject has received any prior antitumor therapy or any investigational anticancer agents.
* Presence of any active autoimmune disease or a history of autoimmune diseases (e.g., interstitial pneumonia, uveitis, enteritis, hepatitis, hypophysitis, vasculitis, myocarditis, nephritis, hyperthyroidism, hypothyroidism \[may be enrolled if stable on hormone replacement therapy\]). Patients with childhood asthma that has completely resolved in adulthood without any intervention, or vitiligo, may be enrolled. Patients requiring medical intervention with bronchodilators are not eligible.
* Known congenital or acquired immunodeficiency, such as Human Immunodeficiency Virus (HIV) infection.
* Uncontrolled cardiac clinical symptoms or diseases, e.g., NYHA Class II or above heart failure, unstable angina, myocardial infarction within 1 year, or patients with clinically significant supraventricular or ventricular arrhythmias requiring clinical intervention.
* Severe concurrent infection within 4 weeks prior to the first dose (e.g., requiring intravenous antibiotics, antifungals, or antivirals), or unexplained fever \>38.5°C during screening/prior to the first dose.
* Known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation.
* Administration of a live attenuated vaccine within 4 weeks prior to the first dose or planned administration during the study period.
* History of or concurrent other malignant tumors within the past 5 years (except for adequately treated basal cell carcinoma of the skin, carcinoma in situ of the cervix, and ovarian cancer).
* Gastrointestinal bleeding event or active hemoptysis within 28 days prior to the first dose.
* Gastric or esophageal varices requiring treatment.
* Active malignant tumors within 36 months prior to enrollment.
* Known allergy to any of the investigational drug components.
* Poorly controlled psychiatric disorder.
* Presence of superior mesenteric vein tumor thrombus, metastasis to group 16 lymph nodes, or distant metastasis to other organs / biological factors: peritoneal metastasis, direct invasion to adjacent organs, etc. / involvement of organs (pancreas, stomach, duodenum, colon) that cannot be resected en bloc.
* Any other condition deemed by the investigator as unsuitable for enrollment. This includes, but is not limited to, pre-existing central nervous system metastases, severe laboratory abnormalities, or familial/social factors that could compromise the subject's safety, or data/sample collection.
* Patients with extensive liver metastases involving the entire liver.