Assessment of cabozantinib treatment on QT interval in a phase 3 study in medullary thyroid cancer: evaluation of indirect QT effects mediated through treatment-induced changes in serum electrolytes.

Purpose: This study evaluated factors impacting QTc interval in a phase 3 trial of cabozantinib in progressive, metastatic, medullary thyroid cancer (MTC).

Methods: Electrocardiogram (12-lead ECG) measurements were obtained at screening, and at pre-dose, and 2, 4, and 6 h post-dose on Days 1 and 29 in a phase 3 study in patients with MTC treated with cabozantinib (140 mg/day). Central tendency analyses were conducted on baseline-corrected QTc values.