Unresectable Biliary Tract Carcinoma

This is a randomized, open-label, two-arm, Phase III clinical trial evaluating the efficacy and safety of trastuzumab plus chemotherapy versus chemotherapy alone as first-line treatment in patients with HER2-positive advanced or metastatic biliary tract cancers (BTC). HER2-positive BTCs represent a molecular subset of these rare cancers, associated with poor prognosis and limited treatment options. Eligible patients with histologically confirmed HER2-positive (IHC 3+ or IHC 2+ with FISH amplification) unresectable or metastatic biliary tract adenocarcinoma-including gallbladder cancer, intrahepatic, and perihilar cholangiocarcinoma-will be randomized in a 1:1 ratio. Participants in the intervention arm (Arm A) will receive either gemcitabine and cisplatin with or without nab-paclitaxel plus trastuzumab, while those in the control arm (Arm B) will receive chemotherapy alone (gemcitabine + cisplatin with or without nab-paclitaxel). Treatment will continue until disease progression, unacceptable toxicity, withdrawal of consent, or death. The primary endpoint is 6-month progression-free survival (PFS). Secondary endpoints include overall survival (OS), response rate (RR), quality of life (QOL), and adverse event (AE) profiles. The study aims to enroll 196 patients across a single center in India over a period of 5 years, with an additional 6-month follow-up. This trial builds on earlier Phase II findings suggesting improved outcomes with trastuzumab in HER2-positive BTC and aims to provide the first randomized evidence for the benefit of HER2-targeted therapy in this setting.

* Clinical trial phase: Phase 2 * Intervention model: Control group * Group allocation: Randomized controlled trial * Research perspective: Prospective study * Participating centers: Multicenter study * Definition of the intervention period: Based on the RECIST 1.1 guidelines, patients will receive treatment until dropout due to disease progression or unacceptable toxicity related to the trial drug. Patients will be followed up with to assess survival every 2 months until either death or the end of the trial, whichever is first. * The intervention period is from the date of IRB approval to December 31st, 2025 * The follow-up duration is one year, and the statistical analysis duration is six months * The total research period is from the date of IRB approval to June 30th, 2026

This study is designed to combine anti-angiogenic drugs on the basis of PD-L1+ gemcitabine/cisplatin, hoping to further improve the curative effect of advanced BTC treatment and provide more choices for first-line treatment of BTC in China.

The sequential treatment strategy of ERCP-RFA combined with envafolimab and surufatinib proposed in this study aims to maximally inhibit the progression of unresectable biliary tract tumors through the combined application of multiple therapeutic modalities. ERCP-RFA, as a local treatment, first reduces the tumor burden and alleviates biliary obstruction through physical ablation. Subsequently, Envafolimab enables the body to more effectively identify and attack the remaining tumor cells by activating the immune system. Finally, Surufatinib as a targeted drug, further controls the growth and spread of tumors by inhibiting tumor angiogenesis and cell proliferation. The potential advantage of this combined treatment lies in the complementary effects of different therapeutic modalities.