New Immunotherapy for Certain Head and Neck Cancers
The FDA has approved the immune checkpoint inhibitor toripalimab for some patients with nasopharyngeal carcinoma.
The U.S. Food and Drug Administration (FDA) has approved toripalimab-tpzi (Loqtorzi), in combination with the chemotherapies gemcitabine (Gemzar) and cisplatin, for the first-line treatment of patients with metastatic, locally advanced, or recurrent nasopharyngeal carcinoma. The FDA has also approved toripalimab as a single agent for nasopharyngeal carcinoma that did not respond to or relapsed following treatment with platinum-based chemotherapy.
Toripalimab is a type of immunotherapy called an immune checkpoint inhibitor (ICI). It blocks the protein PD-1 on immune cells, preventing it from receiving the signals cancer cells use to protect themselves from immune attack. Toripalimab may block PD-1 signaling better than previously approved ICIs; according to a presentation at the 2023 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, toripalimab demonstrated a 12-fold higher binding affinity to PD-1 compared to pembrolizumab (Keytruda).
The approval of toripalimab in combination with gemcitabine and cisplatin was based on results from the phase III, randomized, multicenter, double-blind, placebo-controlled JUPITER-02 trial, which enrolled 289 patients with metastatic nasopharyngeal carcinoma or locally advanced nasopharyngeal carcinoma that recurred after surgery; patients were ineligible if they had previously received chemotherapy in certain disease settings.
Patients were treated with gemcitabine and cisplatin and were randomly assigned to receive either toripalimab or placebo. The median progression-free survival was 11.7 months for patients in the toripalimab arm and eight months for patients in the placebo arm. Similarly, the median overall survival was significantly longer for patients in the toripalimab arm (not reached versus 33.7 months among patients in the placebo arm).
The approval of toripalimab as a monotherapy was based on results from the phase Ib/II, open-label, multicenter, multicohort POLARIS-02 trial. The study enrolled 172 patients with unresectable or metastatic nasopharyngeal carcinoma that had been previously treated with platinum-based chemotherapy or locally advanced nasopharyngeal carcinoma that progressed within six months of platinum-based chemotherapy treatment. The overall response rate was 21%, and the median duration of response was 14.9 months.
Nasopharyngeal carcinoma is a type of head and neck cancer that affects the upper part of the throat, behind the nose. According to federal statistics, it was estimated that around 66,920 individuals would be diagnosed with head and neck cancer and approximately 15,400 patients would die of the disease in the United States in 2023.
The FDA rendered its decision on October 27, 2023.
