According to a story from the ASCO Post, the US Food and Drug Administration (FDA) first approved the drug pembrolizumab as a treatment for advanced esophageal squamous cell carcinoma on July 30th, 2019. The drug was approved for use in patients whose disease displayed certain characteristics. The cancer must be either metastatic or locally advanced; it must express the programmed cell death ligand 1 (PD-L1); and it must have continued to progress after at least one or more treatments with systemic therapy.
About Esophageal Squamous Cell Carcinoma
Esophageal squamous cell carcinoma is a form of esophageal cancer that is generally considered more prevalent in the developing world. It is closely linked to a variety of environmental risk factors, particularly heavy consumption of tobacco and alcohol. Combining these two habits appears to exacerbate risk further. Other risks include chewing betel nuts (a common pastime in some Asian countries), a diet lacking in fresh foods, and consuming very hot beverages. Esophageal cancer is dangerous because it often does not inflict symptoms until it has reached an advanced state. Symptoms include vomiting blood, problems swallowing, enlarged lymph nodes, hoarse voice, and weight loss. Common treatments for the disease include surgery, radiation therapy, and chemotherapy. This cancer only has a chance of cure with surgery if detected in the early stages, which is uncommon; the five year survival rate in the US for all types of esophageal cancer is 15 percent. To learn more about esophageal squamous cell carcinoma, click here.
The approval of pembrolizumab in this indication followed a trial of 628 patients who were randomized to receive either the investigator’s choice of currently available therapy or 200 mg of pembrolizumab every three weeks. Overall, a total of 167 patients from the original pool had disease with the suitable characteristics for treatment with the drug. Patients who received pembrolizumab saw superior results in median overall survival (10.3 months vs 6.7 months), objective response rate (22 percent vs 7 percent), and median progression-free survival (3.2 vs 2.3 months).
This drug functions as an anti PD-1 monoclonal antibody. It binds to this receptor and prevents its activity. This allows the immune system to act on the tumor. The drug is recommended for use until the cancer progresses, toxicity becomes overbearing, or up to 24 months.
Adverse effects include appetite loss, diarrhea, muscle pain, and fatigue.