Abstract CT207: Feasibility of neoadjuvant cabozantinib plus nivolumab followed by definitive resection for patients with locally advanced hepatocellular carcinoma: A Phase Ib trial (NCT03299946)

Long-term outcomes for patients with locally advanced hepatocellular carcinoma (HCC) are poor. Even if clear margins are obtained at the time of surgical resection, most patients with large tumors (>5 cm) relapse due to micrometastatic disease. No therapy has demonstrated clinical benefit in the perioperative setting, underscoring the need for novel therapeutic strategies for resectable HCC. We hypothesize that neoadjuvant therapy resulting in downstaging and elimination of micrometastasis may increase the probability of successful surgical resection. This ongoing open label, single arm Phase Ib trial (NCT03299946) aims to assess the feasibility of neoadjuvant cabozantinib plus nivolumab (CaboNivo) in patients with locally advanced HCC. Targets of cabozantinib include MET and VEGFR. Nivolumab is an immune checkpoint inhibitor targeting PD-1. This study will also allow us to test the hypothesis that cabozantinib primes the tumor microenvironment for anti-PD1 therapy and to study mechanisms of response and resistance to combination therapy. To our knowledge, this is the first neoadjuvant clinical trial of an immune checkpoint inhibitor and the first study of neoadjuvant combination therapy in HCC. 15 patients aged ≥ 18 with potentially resectable HCC that is at high risk of recurrence, ECOG ≤ 1, normal organ and marrow function, and adequate future liver remnant will be enrolled in the study. After 2 weeks of 40 mg daily cabozantinib monotherapy lead-in, patients will receive concurrent 240 mg nivolumab infusions once every 2 weeks for 4 doses. After 8 weeks of neoadjuvant therapy and restaging, patients eligible for resection will proceed to definitive surgical resection ≥ 28 days after the last dose of cabozantinib. Primary outcomes are feasibility and safety of neoadjuvant cabozantinib plus nivolumab. Secondary outcomes are percentage of patients obtaining an R0 resection, pathologic complete response and major pathologic response rates, objective response rate, median overall survival, and median disease free survival. Tumor biopsies from patients at baseline and after 2 weeks of cabozantinib lead-in as well as tumor tissue collected from surgical resection samples will be used to determine the effect of cabozantinib monotherapy and combination therapy with nivolumab on tumor-infiltrating lymphocytes, immune activation and suppression pathways, and cytokine/chemokine signaling. Citation Format: Aleksandra Popovic, Elizabeth Sugar, Anna Ferguson, Bradley Wilt, Jennifer N. Durham, Ihab R. Kamel, Amy Kim, Benjamin Philosophe, Robert A. Anders, Elizabeth M. Jaffee, Daniel Laheru, Matthew J. Weiss, Mark Yarchoan. Feasibility of neoadjuvant cabozantinib plus nivolumab followed by definitive resection for patients with locally advanced hepatocellular carcinoma: A Phase Ib trial (NCT03299946) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT207.