Cabozantinib (Cabometyx, Exelixis) has been approved by the US Food and Drug Administration (FDA) for use in patients with liver cancer. This is a new indication for the oral drug, which is already approved for use in thyroid and renal cancer.
“This new indication for cabozantinib is an important treatment advance for patients with this aggressive form of liver cancer, a community in need of new therapeutic options,” said Michael M. Morrissey, PhD, president and chief executive officer of Exelixis, in a statement.
Cabozantinib is an oral inhibitor of multiple receptor tyrosine kinases, including RET, MET, and vascular endothelial growth factor 2, all of which are involved in both normal cellular function and pathologic processes, such as oncogenesis, metastasis, tumor angiogenesis, and maintenance of the tumor microenvironment.
The drug has been available in the United States since 2012, when it was approved by the FDA as a treatment for patients with medullary thyroid cancer. In 2016, the drug was also approved for use in patients with advanced renal cell carcinoma (RCC) following one prior antiangiogenic therapy. That indication was later expanded to include the treatment of patients with advanced RCC in the first-line setting.
Liver Cancer Survival Improved
The current approval for HCC was based on findings from the phase 3 CELESTIAL trial, which were initially presented at the Gastrointestinal Cancers Symposium 2018, as reported by Medscape Medical News at that time, and was subsequently published in the New England Journal of Medicine.
This trial involved 707 patients with HCC who had experienced disease progression with sorafenib or other systemic therapies. Patients were randomly assigned in a 2:1 ratio to receive 60 mg of cabozantinib orally once daily or placebo.
Results showed that the median overall survival was 10.2 months with cabozantinib vs 8.0 months with placebo; this extrapolated to a 24% reduction in the risk for death (hazard ratio [HR], 0.76; P = .0049). Progression-free survival was also superior with cabozantinib in comparison with placebo (median: 5.2 months vs 1.9 months; HR, 0.44; P < .0001). The overall response rate was 4% in the cabozantinib group compared with 0.4% with placebo (P = .0086).
No patients achieved a complete response in either group. A partial response was seen in 4% of the cabozantinib group and in 0.4% of the group that received placebo. Stable disease was seen in 60% with cabozanitnib vs 33% with placebo; and disease progression occurred in 21% with cabozantinib vs 55% with placebo.
Adverse events were consistent with the known safety profile of cabozantinib. The most common (≥10 %) grade 3 or 4 adverse events seen with cabozantinib vs placebo were palmar-plantar erythrodysesthesia (17% vs 0%), hypertension (16% vs 2%), increased levels of the liver enzyme aspartate aminotransferase (12% vs 7%), fatigue (10% vs 4%), and diarrhea (10% vs 2%).
Last month, Exelixis and its partner Ipsen announced the initiation of a phase 3 trial that is exploring the use of cabozantinib combined with the immunotherapy atezolizumab (Tecentriq, Genentech/Roche) and with sorafenib in previously untreated patients with advanced HCC. This trial, known as COSMIC-312, will also investigate single-agent activity of cabozantinib in the first-line setting of HCC.