Pazopanib(Votrient) is an oral angiogenesis inhibitor targeting vascular endothelial growth factor receptor (VEGFR), platelet derived growth factor receptor (PDGFR), and KIT. These are important pathways for GIST tumors and several trials looked into using pazopanib for GIST. Although initial studies suggested that the drug is not effective for GIST, more recently a phase II study of 25 patients and a randomized study of 86 patients suggest that it is.The results of PAZOGIST, a randomised phase II study of pazopanib plus best supportive care (BSC) vs BSC alone in patients with unresectable metastatic and/or locally-advanced gastrointestinal stromal tumours (GIST), who are resistant or experienced toxicity to previous treatments with standard doses of imatinib and sunitinib, show an improvement in progression-free survival (PFS) in favour of pazopanib arm. The study was presented by Prof. Jean-Yves Blay of the University Claude Bernard Lyon I, Centre Léon Bérard, Lyon, France during the Proffered Paper session in Sarcoma at ESMO Congress 2014 in Madrid, Spain. The primary endpoint was PFS. It was planned to include 80 patients to detect an improvement in the 4-month PFS rate from 15% in the BSC arm alone to 45% in the pazopanib plus BSC with 5% two-sided α error and 80% power. Secondary objectives included overall survival (OS), objective response rate at 4 months, best response rate and tolerance.
P. G. Casali & J.-Y. Blay,Gastrointestinal stromal tumours: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-upAnnals of Oncology 21 (Supplement 5): v98–v102, 2010
nccn, GIST 2012
Nishida T, Hirota S, Yanagisawa A, Sugino Y, Minami M, Yamamura Y, Otani Y, Shimada Y, Takahashi F, Kubota T; GIST Guideline Subcommittee.
Clinical practice guidelines for gastrointestinal stromal tumor (GIST) in Japan: English version.Int J Clin Oncol. 2008 Oct;13(5):416-30.
K. N. Ganjoo et al, A multicenter phase II study of pazopanib in patients with advanced gastrointestinal stromal tumors (GIST) following failure of at least imatinib and sunitinib. Ann Oncol (2014) 25 (1): 236-240.
ESMO Abstract LBA45 – A randomized multicentre phase II study of pazopanib plus best supportive care (BSC) vs BSC alone in metastatic gastroIntestinal stromal tumors (GIST) resistant to imatinib and sunitinib, 2014.
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