**4.7 Pazopanib**

Pazopanib has been tested for advanced thyroid cancer and RET-mutant medullary thyroid cancer [88]. It can be used to treat advanced papillary or follicular thyroid cancer if they express RET gene changes. Pazopanib is an oral small-molecule multi-kinase inhibitor that primarily inhibits vascular endothelial growth factor receptor-1, -2, and -3, platelet endothelial growth factor receptor-α, and -β, and the stem-cell factor receptor c-kit [89]. Pazopanib was introduced as a treatment against various tumors and it has been approved in several countries for advanced soft-tissue sarcoma and renal cell carcinoma. Large clinical trials with pazopanib in patients having soft-tissue sarcoma and renal cell carcinoma have shown beneficial effects. Adverse events include liver dysfunction and hypertension but are generally manageable. Pazopanib has also been used in patients with advanced thyroid cancer [90].
