Treatment with tivozanib, a highly selective and potent vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI), has demonstrated single-agent efficacy in advanced renal cell carcinoma (RCC) along with minimal off-target toxicities and a favorable adverse event (AE) profile. We report final results from TiNivo, a phase Ib/II study of tivozanib combined with nivolumab.In phase Ib, patients with metastatic RCC (mRCC) received tivozanib 1.0 mg once daily (QD) for 21 days followed by 7 days off treatment (n = 3) or tivozanib 1.5 mg QD (n = 3) plus nivolumab 240 mg every 2 weeks (Q2W). The maximum tolerated dose (MTD) was determined to be tivozanib 1.5 mg, and 22 additional patients were enrolled at the MTD for phase II. Primary endpoints included safety and tolerability, with secondary endpoints of objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS).In total, 25 patients were treated with tivozanib 1.5 mg QD (12 [48%] treatment-naïve; 13 [52%] previously treated). Treatment-related grade 3/4 AEs were reported in 20 patients (80%); four patients (17%) experienced AEs that led to dose reduction, and eight (32%) discontinued due to AEs. ORR was 56% (including one complete response) and DCR was 96%, with a median time to best response of 7.9 weeks. Twenty patients (80) had tumor shrinkage. With a median follow-up of 19.0 months (range, 12.6-22.8), median PFS was 18.9 months (95% CI 16.4, not reached) in all patients and was similar in treatment-naïve and previously treated patients.Tivozanib plus nivolumab combination therapy showed a generally tolerable AE profile and promising antitumor efficacy. These results support further development of tivozanib combined with nivolumab as a treatment option in patients with treatment-naïve or previously treated mRCC.