Metastatic renal cell carcinoma treated with pazopanib after progression on other targeted agents: A single-institution experience.

Abstract

351 Background: Pazopanib, a multityrosine kinase inhibitor (TKI), prolongs PFS compared to placebo in treatment-naive and cytokine refractory metastatic renal cell carcinoma (mRCC). No data has been reported about pazopanib salvage therapy after treatment with other targeted agents. Methods: We retrospectively reviewed the records of 88 consecutive patients (pts) with mRCC (median age 62.7, M:F 63/25, 84% clear cell) who received salvage pazopanib between 11/09-8/10. All pts failed previous treatment with one or more targeted agents (median number of prior targeted agents was 2, range 1-5; median time on previous treatments was 632 days). 78% of pts had progressed on sunitinib, 40% on sorafenib, 20% on temsirolimus, 51% on everolimus, and 26% on bevacizumab. 26% received previous chemotherapy and 16% received previous cytokines in addition to targeted therapies. 58% failed both TKI/VEGF inhibitors and mTOR inhibitors. 57% had intermediate-risk disease and 43% had poor-risk disease by MSKCC criteria. All pts had follow-up at least every 3 months after initiating pazopanib. Results: Median time to last follow-up was 114 days (range 30-278 days). 42% continued pazopanib at last follow- up. 25% had partial response (PR) by treating physician assessment. 50% failing 1-2 previous targeted therapies remained on pazopanib at last follow-up, compared to 27% of those failing more than 2 targeted therapies (p=0.04). 56% of pts with intermediate-risk disease by MSKCC criteria continued pazopanib at follow-up compared to 27% with poor-risk disease (p=0.002). 42% of those failing 1 prior targeted therapy achieved PR compared to 18% failing >1 prior targeted therapy (p=0.02). 35% discontinued pazopanib due to progressive disease (PD) (median time to PD 71 days, range 36-198 days), 10% discontinued due to adverse drug events, and 10% died of PD on treatment. There were no treatment related deaths. Conclusions: In this retrospective study, pazopanib demonstrated clinically relevant activity in mRCC following PD with other targeted therapies. Mature survival data will be provided with final presentation. No significant financial relationships to disclose.