On second thought, the FDA figures it no longer needs to discuss Exelixis’ application for Cabometyx in neuroendocrine tumors at an advisory committee meeting.
Exelixis disclosed the cancellation Thursday while confirming that the FDA's original April 3 target decision date for the filing remains.
Citi analysts interpreted the shift as a positive sign for Exelixis’ bid, postulating in a Thursday note that the agency came around to its decision “given the strength” of Cabometyx’s dataset.
Exelixis’ original announcement about a planned advisory committee meeting came as somewhat of a surprise given doctors’ positive feedback about the findings from the drug’s phase 3 Cabinet trial, which was sponsored by the National Cancer Institute.
At the final analysis of the study, Cabometyx reduced the risk of progression or death by 77% compared with placebo in patients with heavily pretreated advanced pancreatic neuroendocrine tumors (pNET) or by 62% in those with extra-pancreatic neuroendocrine tumors (epNET), according to data presented at the European Society for Medical Oncology Congress 2024.
The huge progression-free survival benefits immediately prompted talk about Cabometyx’s potential to become a new standard of care in NET patients with progressive disease, who currently don’t have a clear treatment option available.
So when news came in November that the FDA was convening a meeting of the Oncology Drugs Advisory Committee, Leerink partners analysts suspected that the agency might have questions about the drug’s safety and overall survival data.
Cabometyx’s massive tumor progression improvements somehow didn’t translate into statistically significant overall survival benefits, which might have raised uncertainties at the FDA, Leerink analysts previously noted. Numerically, the drug cut the risk of death by 5% in patients with pNETs and by 14% in those with epNETs.
The Exelixis drug also showed far higher rates of discontinuation due to adverse events or dose reductions compared with placebo.
Both Novartis’ Afinitor and Pfizer’s Sutent had gone through an advisory committee meeting and came out triumphant before their respective NET approvals. Given that history, plus Cabometyx’s “outsized” benefit without unexpected tolerability events, William Blair analysts in November said they were confident about the drug’s eventual approval.
Separately, Exelixis has said it plans to submit Cabometyx, used in combination with Roche’s Tecentriq, for metastatic castration-resistant prostate cancer with the FDA by the end of 2024. That application faces more uncertainty because of a lack of an overall survival showing at the final analysis of the phase 3 Contact-02 trial. Thanks to that finding, Exelixis’ partner Ipsen has already decided not to file for the indication in Europe.