AstraZeneca have announced results from a phase II study evaluating the investigational drug vandetanib for the treatment of patients with locally advanced or metastatic papillary or follicular thyroid cancer.
This study, ZACTHYF, showed that treatment with vandetanib significantly improved Progression Free Survival (PFS), the primary endpoint of the study, compared to placebo (Hazard Ratio=0.63, p=0.008). Median PFS was improved by 5 months (11.0 months for vandetanib and 5.8 months for placebo patients). The results of the ZACTHYF study were presented today at the International Thyroid Congress in Paris.
ZACTHYF is a phase II, randomised, double blind, placebo controlled, multi-centre study, which compared oral once-daily vandetanib 300mg to placebo in 145 patients with locally advanced or metastatic papillary or follicular thyroid cancer who failed treatment with, or were unsuitable for, radioiodine therapy.
“Papillary and follicular thyroid cancer are the most common forms of thyroid cancer and these results show evidence of vandetanib activity in patients with advanced metastatic disease where there are few treatment options after surgery and treatment with radioactive iodine,” said Peter Langmuir, M.D. Executive Director, Medical-Science, AstraZeneca, “This adds to previous data which shows vandetanib to be the first therapy to demonstrate improved efficacy vs placebo in a phase III trial in patients with advanced medullary thyroid cancer”.
There were no significant differences observed in ZACTHYF between vandetanib and placebo groups across the secondary efficacy endpoints of objective response rate, disease control rate at six months and overall survival. The safety profile of vandetanib is consistent across all thyroid studies. The most common adverse events are diarrhoea, asthenia, fatigue, hypertension, decreased appetite, nausea, acne, rash and QTc prolongation.
AstraZeneca plans regulatory submissions in 2010 for the treatment of patients with advanced medullary thyroid cancer.
Vandetanib is thought to work by inhibition of the vascular endothelial growth factor (VEGF) pathway, epidermal growth factor receptor (EGFR) and rearranged during transfection (RET) pathways.