Is Axitinib Still a Valid Option for mRCC in the Second-Line Setting? Prognostic Factor Analyses From the AXIS Trial.

Background: Axitinib resulted in significantly longer progression-free survival (PFS) versus sorafenib in patients with metastatic renal-cell carcinoma (mRCC) previously treated with sunitinib in the AXIS trial. We report post hoc analyses evaluating patient subgroups that may benefit more from axitinib in this setting.

Patients And Methods: AXIS was an open-label randomized phase 3 trial (NCT00678392) in mRCC patients with disease that failed to respond to one prior systemic therapy. Univariate and multivariate analyses evaluated potential prognostic factors for improved PFS and overall survival (OS) after sunitinib. PFS and OS of axitinib versus sorafenib were assessed within subgroups identified according to these factors.

Results: Of 723 patients, 389 received first-line sunitinib; 194 and 195 were randomized to second-line axitinib and sorafenib, respectively. Identified prognostic factors were: nonbulky disease (sum of the longest diameter < 98 mm), favorable/intermediate risk disease (Memorial Sloan Kettering Cancer Center or International Metastatic Renal Cell Carcinoma Database Consortium criteria), and no bone or liver metastases. In patients with all of these prognostic factors (n = 86), significantly longer PFS was observed for axitinib versus sorafenib (hazard ratio = 0.476; 95% confidence interval, 0.263-0.863; 2-sided P = .0126). OS (hazard ratio = 0.902; 95% confidence interval, 0.457-1.780; 2-sided P = .7661) was similar between treatments. Across subgroups, PFS was generally longer in patients treated with axitinib versus sorafenib, and OS was generally similar between the two treatments.

Conclusion: In patients with mRCC, axitinib remains a suitable second-line treatment option across multiple subgroups. A relevant reduction in the risk of a PFS event was observed for axitinib compared to sorafenib in selected subgroups of patients.