Real-world Effectiveness of Single-Agent Tivozanib in Patients with Metastatic Clear Cell Renal Cell Carcinoma

Tivozanib, a selective vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor, is approved for relapsed or refractory metastatic clear cell renal cell carcinoma (mccRCC). However, real-world evidence of its effectiveness is limited. Herein, we sought to assess the real-world outcomes of single-agent tivozanib in patients with mccRCC. This retrospective study utilized the US-based Flatiron Health electronic health record-derived de-identified database. Patients with mccRCC who received single-agent tivozanib were included. Primary endpoints were real-world time to next treatment (rwTTNT) and real-world overall survival (rwOS). rwTTNT was defined as time from start of tivozanib to next therapy or death, and rwOS as time from start of tivozanib to death, with both censored at loss to follow-up. Median rwTTNT and rwOS with 95% confidence intervals (CIs) were estimated using Kaplan-Meier estimator, stratified by the line of therapy. Of the 13,909 patients with renal cell carcinoma in the dataset, 9,732 had clear cell histology. Among these, 145 patients treated with single-agent tivozanib were included in the analysis. The median age was 68 years (IQR, 61-73 years), and 67.6% were males. rwTTNT and rwOS in the third-line therapy setting were 6.9 (95% CI 3.4, 11) and 11.0 (95% CI 8, 21) months, respectively, and in the fourth-line setting were 4.7 (95% CI 3.6, 7.5) and 8.4 (95% CI 7.2, 20) months, respectively. In summary, single-agent tivozanib potentially provides clinically meaningful benefits in heavily pretreated patients with mccRCC. These findings support its role as a useful later-line therapeutic option in mccRCC management.