New Brunswick, N.J. – A clinical trial testing the immunotherapy drug pembrolizumab is showing the drug to be well tolerated among patients who have carcinoid or pancreatic neuroendocrine tumors. Janice M. Mehnert, MD, director of the Phase I and Developmental Therapeutics Program at Rutgers Cancer Institute of New Jersey, is the lead author of research that is part of an oral presentation at the European Society for Medical Oncology 2017 Congress taking place later this week in Madrid, Spain. Dr. Mehnert, who is also a medical oncologist in the Melanoma and Soft Tissue Oncology Program at Rutgers Cancer Institute, shares more about the work, conducted by a collective of international investigators.
Q: Why explore immunotherapy in these particular patient populations?
A: Immunotherapy drugs put the body’s natural defenses back to work by targeting the PD-L1 protein and PD-1 receptor and blocking their ability to prevent T cells from destroying cancer cells. Pembrolizumab has shown anti-tumor activity in advanced malignancies including melanoma and non-small cell lung cancer. With treatment options being limited for patients with carcinoid and pancreatic neuroendocrine tumors, it is imperative to explore new therapy options for these populations.
Q: How was the study structured?
A: At the time our abstract was submitted, 25 participants who presented with advanced carcinoid tumors and 16 patients with pancreatic neuroendocrine tumors were accrued from multiple international sites. Participants received 10 mg of pembrolizumab for up to 24 months or until confirmed progression or intolerable toxicity. Safety, tolerability and response were assessed every eight weeks for the first six months and every 12 weeks thereafter.
Q: What did you find?
A: At the time our results were reported we discovered findings similar to other trials of immunotherapy agents, with the majority of patients actually not responding to therapy. 12 percent of patients with carcinoid tumors and six percent of patients with pancreatic neuroendocrine tumors experienced a response to therapy. However, patients who achieved response were likely to have durable control of their disease, with all responses greater than or equal to six months in duration. Therapy was overall well tolerated and safe, with some side effects related to autoimmune processes caused by the medication.
Q: What is the implication of these findings?
A: These findings are interesting but need further validation in larger studies of patients with carcinoid and pancreatic neuroendocrine tumors. As well, investigative work focusing on identifying valuable biomarkers that could help predict which patients would respond to treatment with these agents is critical. Discoveries in this realm would improve the selection of patients for this particular therapeutic approach.