Study on Cabozantinib vs. Placebo for Thyroid Cancer Resistant to Radioiodine and Previous VEGFR Therapy

Inclusion Criteria

• Have a confirmed diagnosis of differentiated thyroid cancer.
• Have cancer that can be measured using standard criteria.
• Have been treated with or are not eligible for iodine-131 treatment for thyroid cancer.
• Have previously been treated with at least one VEGFR-targeting drug, such as lenvatinib or sorafenib, for thyroid cancer. Up to two such treatments are allowed.
• Be in good overall health with an ECOG performance status of 0 or 1, meaning fully active or restricted in physically strenuous activity but ambulatory.

Exclusion Criteria

• Have previously been treated with cabozantinib, a BRAF inhibitor, more than two VEGFR-targeting drugs, more than one immune checkpoint inhibitor, or more than one chemotherapy regimen.
• Have taken any small molecule kinase inhibitor within two weeks or five half-lives of the drug before starting the study.
• Have received any anticancer antibody or chemotherapy within four weeks before starting the study.
• Have had radiation therapy for bone metastasis within two weeks or any other radiation therapy within four weeks before starting the study.
• Have known brain metastases or disease in the brain's outer layer unless it has been adequately treated.