Activity of cabozantinib in further line treatment of metastatic clear cell renal cell carcinoma. Real-world experience in a single-center retrospective study.

ABSTRACT

Introduction: Cabozantinib is an oral inhibitor of MET, AXL, and vascular endothelial growth factor receptors. It has an immunomodulatory effect and may influence the tumor's microenvironment and make mutated cells more sensitive to immune-mediated killing. These properties have made cabozantinib an effective drug for first-line or subsequent-line treatment after progression of metastatic renal cell carcinoma (mRCC), even after immunotherapy. Material and methods: Seventy-one patients with mRCC were treated with second or further lines of cabozantinib at the Department of Genitourinary Oncology, Maria Sklodowska-Curie National Research Institute of Oncology. This study retrospectively evaluated the effectiveness of cabozantinib in subsequent lines of treatment. Progression-free survival (PFS) and overall survival (OS) were the primary endpoints. The best overall response (BOR) to cabozantinib was the secondary endpoint. For this purpose, Cox's proportional hazard model was used. Results: The median PFS was 11 months (5; 23) and the median OS was 16 months (10; 42) and differed significantly in the second and further lines of treatment. Progression in the second and further lines was observed in 28 (93%) and 27 (66%) patients, respectively (p = 0.006). Partial response as the BOR was observed in one patient (3%) in the second line and 13 patients (32%) in the further lines (p = 0.012). Conclusions: Cabozantinib has antitumor effects in the second and further lines of treatment. In this study we observed high efficiency of cabozantinib in further lines of treatment.