FDA Approves Cabometyx for Advanced Neuroendocrine Tumors

The US Food and Drug Administration (FDA) has officially approved Exelixis’ Cabometyx (cabozantinib) for the treatment of advanced neuroendocrine tumors (NETs). This approval extends to both adult and pediatric patients aged 12 and older who have previously undergone treatment for unresectable, locally advanced, or metastatic well-differentiated pancreatic NETs or extra-pancreatic NETs.

Neuroendocrine tumors are a type of cancer that arises from neuroendocrine cells located in the digestive tract and other organs, including the lungs and pancreas. In the United States alone, there were approximately 380,000 cases reported last year. Generally, NETs are characterized by their slow development over several years. However, patients with advanced or metastatic forms of these tumors eventually experience disease progression and resistance to treatment.

Cabometyx functions by inhibiting tyrosine kinase enzymes, which play a role in the transmission of growth signals in cancer cells. It is already approved for the treatment of certain cases of renal cell carcinoma, hepatocellular carcinoma, and differentiated thyroid cancer within the United States.

The FDA's recent decision is informed by encouraging outcomes from the CABINET trial, a late-stage study that compared Cabometyx to a placebo in patients with advanced pancreatic or extra-pancreatic NETs who had previously received treatment. Results of the trial indicated that Cabometyx significantly improved progression-free survival (PFS), the primary endpoint of the study. In participants with pancreatic NETs, the median PFS achieved with Cabometyx was 13.8 months, compared to just 4.4 months in the placebo group, based on a median follow-up duration of 13.8 months. For those with extra-pancreatic NETs, the median PFS was 8.4 months for Cabometyx and 3.9 months for placebo, with a median follow-up of 10.2 months.

Jennifer Chan of the Dana-Farber Cancer Institute, who chaired the CABINET trial, noted the variability in NET characteristics among patients and the limited treatment options available. She remarked on the significance of this FDA approval as it introduces a potentially transformative treatment option for individuals with these tumors, regardless of their somatostatin receptor expression and functional status.

Exelixis retains exclusive rights to develop and market Cabometyx within the United States. Outside the US and Japan, Ipsen holds exclusive marketing rights, while Takeda has been granted these rights within Japan.