Tivozanib as first-line treatment of metastatic renal cell carcinoma: A real-world outcome review in North-West of England, United Kingdom.

Abstract

638 Background: Tivozanib is a selective tyrosine kinase inhibitor (TKI) of vascular endothelial growth factor and has been shown to offer PFS and tolerance advantage compared to sorafenib among patients with mRCC. In this retrospective review, we aim to investigate the real world efficacy and tolerance of tivozanib delivered in four cancer hospital in the Northwest of England. Methods: mRCC patients started tivozanib in first line setting were identified and reviewed. Primary outcomes of interest include overall response rate (ORR), survival (OS, PFS where possible) and treatment tolerance. Results: A total of 113 patients were identified between March 2017 and May 2019. Median follow up was 200 days (15-792). 26% were switched from other prior TKI due to intolerance. 28%, 48% and 24% had Favourable (F), Intermediate (I) and Poor(P) IMDC risk category respectively. ORR was 29% (CR 0%, PR29%, SD38%, PD26%, NE 7%). Median PFS (after 53 events) was 9 months (F = NR, I = 7 months, P = 3 months p value < 0.0001) with estimated 6 and 12 months OS of 80% and 67 % respectively. At cut-off, 26/32 with F IMDC risk remaining on treatment c.f. 24/54 (I) and 6/27 (P). Median treatment received was 5 cycles and 65% still on full dose at end of observation. Dose reduction was necessary in 31% while treatment was stopped in 15% due to toxicity. 46% received subsequent therapy post- progression. The commonest adverse events were fatigue (32%, G3 0%), diarrhoea (15%, G3 1.7%), mucositis (15%, G3 < 1%), and anorexia (7%, G3 1.7%). Conclusions: Preliminary findings from this review suggests similar clinical efficacy of tivozanib compared to agents such as pazopanib or sunitinib in real-world setting particularly among patient with Favourable IMDC category however longer follow up is required to fully evaluate this. Treatment is well tolerated with low incidence of severe grade toxicities and may be a good monotherapy option in patient of Favourable IMDC category unsuitable for combination therapies.