Combining Immunotherapy and Chemotherapy to Treat Esophageal Cancer 

the immunotherapeutic pembrolizumab in combination with chemotherapy WAS APPROVED to treat certain adult patients with esophageal cancer. 

The U.S. Food and Drug Administration (FDA) recently approved the immune checkpoint inhibitor pembrolizumab (Keytruda) in combination with platinum and fluoropyrimidine-based chemotherapy for patients with metastatic or locally advanced esophageal cancer or with gastroesophageal (GEJ) tumors. The combination therapy is indicated for patients who are not candidates for surgical removal of their tumors or for definitive chemoradiation. 

esophageal adenocarcinoma
Esophageal adenocarcinoma. Image via Wikimedia Commons.

Pembrolizumab blocks the function of an immune-suppressing protein called PD-1, which is found on immune cells called T cells. The inhibition of PD-1 by pembrolizumab removes the brakes from the T cells, so they can attack and destroy the cancer cells. 

The data to demonstrate the efficacy of combining pembrolizumab with chemotherapy was collected in a multicenter, randomized, placebo-controlled trial that enrolled 749 patients with metastatic or locally advanced esophageal or GEJ tumors. Patients were randomized to either receive pembrolizumab in combination with chemotherapy or a placebo with chemotherapy.  

The median overall survival was 12.4 months for the patients who received pembrolizumab and chemotherapy versus 9.8 months for patients who received placebo and chemotherapy. The median progression-free survival was 6.3 months for those in the pembrolizumab and chemotherapy arm of the study versus 5.8 months for the patient group that received a placebo with chemotherapy. 

According to federal statistics, more than 19,000 new cases of esophageal cancer were expected to be diagnosed in the U.S. in 2021. Gastroesophageal tumors represent a rare, but highly aggressive, subset of esophageal cancer. 

The FDA rendered its approval on March 22, 2021.