Real-world data on the efficacy and safety of pazopanib in IMDC favorable- and intermediate-risk metastatic renal cell carcinoma: a multicenter retrospective cohort study of Chinese patients

BACKGROUND: Pazopanib was recommended as first-line treatment option for Metastatic renal cell carcinoma (mRCC), while evidence from strictly selected patients has poor external validity and clinical characteristics are complex in real-world clinical practice. This study aimed to illustrate the survival benefits and safety of pazopanib monotherapy using real-world data of mRCC patients. METHODS: This was a retrospective, multicenter, cohort study. We recruited adult patients with International Metastatic renal cell carcinoma Database Consortium (IMDC) favorable- and intermediate-risk mRCC receiving first-line pazopanib from May 2017 to February 2020. Patients were treated with pazopanib 800 mg or 600 mg orally once daily. Treatment efficacy, and drug safety were analyzed. Response was evaluated using the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Drug safety was assessed according to the grade of treatment-related adverse reactions. RESULTS: Based on IMDC risk stratification, there were 46 (32.2%) patients in the favorable-risk group and 97 (67.8%) patients in the intermediate-risk group. The median progression-free survival (PFS) of the entire cohort, favorable- and intermediate risk groups was 21.2, 27.1 and 17.2 months, respectively. In the intermediate-risk group, PFS was much longer in patients with 1 risk factor than in patients with 2 risk factors, with a median of 25.9 months versus 11.2 months (P<0.0001). Patients with lung metastasis only had longer PFS than those with bone metastasis only, with a median PFS of 25.9 vs. 21.2 months, respectively. Furthermore, local therapy for the metastatic site appeared to benefit patients in the IMDC favorable-risk group but not those in the IMDC intermediate-risk group. The best response was 40/140 (29%) partial response (PR), 86/140 (61%) stable disease (SD), and 14/140 (10%) progressive disease (PD). The most common adverse drug reactions (ADRs) were change in hair color (47.7%), hypertension (40.0%), diarrhea (40.0%), proteinuria (38.5%), elevation of transaminase (35.4%), and hand–foot skin reaction (32.3%). CONCLUSIONS: This real-world data analysis recommended that patients in intermediate-risk group need to be further stratified according to the number of risk factors. Pazopanib was most suitable for patients with lung metastasis only. Local treatment for metastatic lesions should only be recommended in IMDC favorable patients.