Hypertension and myelosuppression as biomarkers of sunitinib efficacy in Chinese patients (pts) with metastatic renal cell carcinoma (mRCC).
426 Background: In an open-label, phase IV study of sunitinib as 1st-line treatment (Tx) in Chinese pts with mRCC, median progression-free survival (PFS) and overall survival (OS) were 61.7 and 133.4 wk, respectively; objective response rate (ORR) was 31.1% (Ann Oncol 2012;23:851P). We retrospectively investigated correlations between on-Tx hypertension (HTN), neutropenia (N), and thrombocytopenia (T) and efficacy endpoints in pts from this trial. Methods: HTN was defined by either maximum systolic blood pressure ≥140 mm Hg (S-HTN) or maximum diastolic blood pressure ≥90 mm Hg (D-HTN). Using CTCAE assessment, N grade ≥2 and T grade >1 were used as cut-points for the analyses. Median PFS and OS were estimated by Kaplan−Meier method. The log-rank test was used to compare PFS and OS between groups with and without HTN, N grade ≥2, or T grade >1. Fisher’s exact test was used for ORR. Results: 102 pts were included in the HTN analyses, 60% with S-HTN versus 40% without S-HTN. Pts with S-HTN had greater ORR and longer PFS and OS than pts without S-HTN (Table). (Results were similar with D-HTN; see Table.) 103 pts were included in the N and T analyses, 67% with N grade ≥2 versus 33% with N grade <2, and 56% with T grade >1 versus 44% with T grade ≤1. Pts with N grade ≥2 had significantly greater ORR and significantly longer PFS and OS than pts with N grade <2 (Table). Pts with T grade >1 had greater ORR and significantly longer PFS and OS than pts with T grade ≤1 (Table). Conclusions: The developments of N grade ≥2 and T grade >1 during Tx with sunitinib were significantly associated with better outcome. Median PFS was more than twice as long for pts with S-HTN as for those without S-HTN, but the association did not reach statistical significance. [Table: see text]