A phase II single arm study of Nivolumab with stereotactic Ablative radiation Therapy after induction chemotherapy in CHOlangiocarcinoma (NATCHO)

BACKGROUND: Intrahepatic cholangiocarcinoma (CCA) is amongst the most common primary liver tumors worldwide. CCA carries a bad prognosis prompting research to establish new treatment modalities other than surgery and the current chemotherapeutic regimens adopted. Hence, this trial explores a new therapeutic approach, to combine stereotactic body radiation therapy (SBRT) and immunotherapy (Nivolumab), and asses its clinical benefit and safety profile after induction chemotherapy in CCA. METHODOLOGY: This is a Phase II open-label, single-arm, multicenter study that investigates Nivolumab (PD-1 inhibitor) treatment at Day 1 followed by SBRT (30 Gy in 3 to 5 fractions) at Day 8, then monthly Nivolumab in 40 patients with non-resectable locally advanced, metastatic or recurrent intrahepatic or extrahepatic CCA. Eligible patients were those above 18 years of age with a pathologically and radiologically confirmed diagnosis of non-resectable locally advanced or metastatic or recurrent intrahepatic or extrahepatic CCA, following 4 cycles of cisplatin-based chemotherapy with an estimated life expectancy of more than 3 months, among other criteria. The primary endpoint is the progression free survival (PFS) rate at 8 months and disease control rate (DCR). The secondary endpoints are overall survival (OS), tumor response rate (TRR), duration of response, evaluation of biomarkers: CD3 + , CD4 + and CD8 + T cell infiltration, as well as any change in the PD-L1 expression through percutaneous core biopsy when compared with the baseline biopsy following 1 cycle of Nivolumab and SBRT. DISCUSSION: SRBT alone showed promising results in the literature by both inducing the immune system locally and having abscopal effects on distant metastases. Moreover, given the prevalence of PD-L1 in solid tumors, targeting it or its receptor has become the mainstay of novel immunotherapeutic drugs use. A combination of both has never been explored in the scope of CCA and that is the aim of this study. TRIAL REGISTRATION: ClinicalTrials.gov NCT04648319, April 20, 2018. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-022-10373-1.