Axitinib in advanced renal cell carcinoma: Outcomes following pazopanib or sunitinib.

Abstract

609 Background: Axitinib is licensed in Europe for the treatment of adult patients with advanced renal cell carcinoma after failure of sunitinib, but not pazopanib. Efficacy is based on the AXIS trial which reported a progression free survival (PFS) of 4.8 months and an overall survival (OS) of 15.2 months in patients who had received prior sunitinib. Despite widespread use of pazopanib in the first line setting there is no randomised trial evidence to support the use of axitinib after pazopanib. The Beatson Cancer Centre (BCC) renal cancer clinic provides all systemic therapy for a population of 2.8 million. Within BCC axitinib is used post sunitinib or pazopanib. We performed an analysis of patient outcomes in patients who commenced axitinib in WOS between November 2013 and November 2014. Methods: Data were collected prospectively from the electronic clinical records. Duration of treatment was used as a surrogate for progression free survival (PFS). Data were analysed in April 2015 which served as the censor date for those still alive. Results: 46 patients were included. At the time of analysis 38 patients had stopped axitinib and 30 patients had died. 22 patients (48%) had received prior pazopanib and 21 (46%) prior sunitinib. For the patients who received axitinib in the 2nd line setting (n = 38) median duration of treatment was 4.8 months (95% CI 0.55 – 9.12). Median duration post sunitinib and pazopanib was 4.8 months (95% CI 0 – 9.7) and 5.3 months (95% CI 2.2- 8.4). Median OS was 9.2 months (95% CI 6.44 – 12.05) overall and 9.44 months (95% CI 5.36 – 13.5) and 8.36 months (95% CI 1.7 – 11.6) post sunitinib and pazopanib respectively. Conclusions: PFS appears to be comparable to reported trial data irrespective of first line treatment indicating similar efficacy and tolerability in real life. We found no evidence of a significant difference in OS regardless of first line treatment which supports the current practice of using axitinib post sunitinib or pazopanib. The inferior OS compared to AXIS trial could be multifactorial and requires further investigation.