Radioactive iodine–refractory differentiated thyroid cancer (RAIR-DTC) is a rare and aggressive form of thyroid cancer that does not respond to radioactive iodine treatment, which is the standard treatment for most types of thyroid cancer. RAIR-DTC is typically diagnosed when cancer cells continue to grow or spread despite receiving radioactive iodine therapy, which can result in a poor prognosis and limited treatment options for patients. There is a significant unmet need for effective treatments for RAIR-DTC, and clinical trials are ongoing to evaluate new therapies that may provide hope for patients with this challenging disease.
Apatinib, a highly selective vascular endothelial growth factor (VEGFR-2) inhibitor, is being studied as a possible treatment option for these patients.
A phase 3 randomized clinical trial was conducted on 92 patients with progressive locally advanced or metastatic RAIR-DTC to evaluate the efficacy and safety of apatinib. The trial was conducted in 21 sites between February 17, 2017, and March 2, 2020.
The patients were randomly assigned (1:1) to receive apatinib, 500 mg/d, or a placebo. Patients who developed progression while receiving placebo were allowed to cross over to apatinib.
The primary endpoint of the study was investigator-assessed progression-free survival (PFS). Secondary endpoints included overall survival, objective response rate (ORR), disease control rate (DCR), duration of response, time to objective response, and safety.