On April 25, 2016, the U.S. Food and Drug Administration (FDA) approved cabozantinib (Cabometyx) tablets for the treatment of advanced renal cell carcinoma in patients who have received prior antiangiogenic therapy. Cabozantinib is a dual tyrosine kinase inhibitor of MET and VEGFR2. The capsule formulation of cabozantinib (Cometriq) was previously approved for the treatment of metastatic medullary thyroid carcinoma.
The approval was based on the randomized phase III METEOR trial, in which patients with advanced renal cell carcinoma who had received prior antiangiogenic therapy received either cabozantinib at 60 mg orally once daily (N = 330) or everolimus at 10 mg orally once daily (N = 328).
The primary endpoint was progression-free survival among the first 375 randomized subjects. Median progression-free survival in this group was 7.4 and 3.8 months in the cabozantinib and everolimus arms, respectively (hazard ratio [HR] = 0.58, 95% confidence interval [CI] = 0.45–0.74; P < .0001). Median overall survival in the intent-to-treat population was 21.4 and 16.5 months in the cabozantinib and everolimus arms, respectively (HR = 0.66, 95% CI = 0.53–0.83; P = .0003). Confirmed response rate was 17% (95% CI = 13%–22%) in the cabozantinib arm and 3% (95% CI = 2%–6%) in the everolimus arm.
Safety and Toxicity
Safety was evaluated in 331 patients treated with cabozantinib. The most common (≥ 25%) adverse reactions included diarrhea, fatigue, nausea, decreased appetite, palmar-plantar erythrodysesthesia syndrome, hypertension, vomiting, weight loss, and constipation. Sixty percent of patients treated with cabozantinib had at least one dose reduction while on study. Serious adverse events were reported in 40% of patients. The most common serious adverse events (≥ 2%) were abdominal pain, pleural effusion, diarrhea, and nausea.
The recommended dose and schedule for cabozantinib is 60 mg orally daily. For more information visit FDA.gov. ■