Median time to progression with TKI-based therapy after failure of immuno-oncology therapy in metastatic kidney cancer: A systematic review and meta-analysis

BACKGROUND: The efficacy of tyrosine kinase inhibitor (TKI)-based therapy after previous immuno-oncology therapy (IO) failure has been addressed before. However, summary efficacy estimates have never been generated in these reports. We addressed this void.

MATERIAL AND METHODS: We systematically examined TKI efficacy after IO-failure and generated weighted median progression-free survival (PFS) estimates for Pazopanib, Axitinib, Cabozantinib, Sunitinib. A systematic review according to PRISMA was conducted. PubMed and abstracts were queried. Only studies proving median PFS were included. Weighted medians were computed for each TKI alternative.

RESULTS: Of 245 articles, nine eligible studies were included in the current study with 952 analysed patients. Weighted PFS medians after any previous IO-based therapy were respectively 13.7 (range from 4.6 to 24.4), 8.1 (range from 4.7 to 13.2), 8.5 (range from 4.7 to 15.2) and 6.9 months (range from 2.9 to 11.6) for Pazopanib, Axitinib, Cabozantinib, Sunitinib. Specific second-line weighted PFS median was 14.8 months (range from 5.6 to 24.4), 10.1 months (range from 6.4 to 13.2), 8.7 months (range from 4.7 to 15.2) and 6.0 months (range from 2.9 to 8.0) for Pazopanib, Axitinib, Cabozantinib, Sunitinib, respectively, after first-line IO.

CONCLUSION: Pazopanib results in the longest weighted median PFS, after previous IO-failure, regardless of treatment line, as well as in specific second-line, post-first-line IO failure settings. Pending novel studies, Pazopanib appears to represent the most promising treatment option after prior IO.