A Study of Cabozantinib Compared With Placebo in Subjects With Radioiodine-refractory Differentiated Thyroid Cancer Who Have Progressed After Prior Vascular Endothelial Growth Factor Receptor (VEGFR) -Targeted Therapy

Prior treatment

• Prior treatment with any of the following: Cabozantinib; Selective small-molecule v-raf murine sarcoma viral oncogene homolog B1 (BRAF) kinase inhibitor; More than 2 VEGFR-targeting TKI agents; More than 1 immune checkpoint inhibitor therapy; 1 systemic chemotherapy regimen (given as single agent or in combination with another chemotherapy agent)
• Receipt of any type of small molecule kinase inhibitor (including investigational kinase inhibitor) within 2 weeks or 5 half-lives of the agent, whichever is longer, before randomization
• Receipt of any type of anticancer antibody (including investigational antibody) or systemic chemotherapy within 4 weeks before randomization
• Receipt of radiation therapy for bone metastasis within 2 weeks or any other radiation therapy within 4 weeks before randomization.

Other illness

• Known brain metastases or cranial epidural disease unless adequately treated

• Histologically or cytologically confirmed diagnosis of Differentiated Thyroid Cancer (DTC)
• Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1
• Previously treated with or deemed ineligible for treatment with Iodine- 131 for differentiated thyroid cancer (DTC)
• Previously treated with at least one of the following vascular endothelial growth factor receptor (VEGFR)-targeting tyrosine kinase inhibitor (TKI) agents for DTC: lenvatinib or sorafenib. Note: Up to two prior VEGFR-targeting TKI agents are allowed
• Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1