The therapeutic efficacy of metastatic renal cell carcinoma (mRCC) has been significantly enhanced with the advent of immune checkpoint inhibitors (ICIs). However, there are limited data on the efficacy of Tislelizumab in patients with mRCC. This study aimed to assess the effectiveness and safety of Tislelizumab plus tyrosine kinase inhibitor (TKI) for patients with mRCC.

Demographic and clinicopathological data of mRCC patients treated with first-line TKI monotherapy or Tislelizumab plus TKI therapy between March 2019 to February 2023 were collected. Outcome measures included the objective response rate (ORR), median progression-free survival (mPFS). Patient baseline characteristics and adverse events (AEs) were documented.

Totally 136 patients were included in the analysis, with a median age of 57 years. Of the patients, 72.1% were male, 78.8% with intermediate/poor-risk disease. For the overall population, the combination group (n = 61) exhibited a longer PFS compared to the TKI monotherapy group (n = 75) (mPFS (95% CI): 15.9 (10.9–20.9) vs. 6.2 (5.4–6.9) months, P < 0.001) and improved ORR (44.3% vs. 18.7%, P = 0.001). In the non-clear cell RCC (nccRCC) subgroup (n = 39), the combination group (n = 20) showed improved PFS (mPFS (95% CI): 11.9 (0.6–23.3) vs. 4.6 (3.4–5.9) months, P < 0.001) and ORR (40.0% vs. 10.5%, P = 0.006) compared to the TKI monotherapy group (n = 19). The incidence of grade three or higher treatment-related AEs are comparable between the groups (47.54% vs. 40.00%).

Our data demonstrated the promising efficacy and safety profile of Tislelizumab plus TKI as first-line treatment for both ccRCC and nccRCC.