MedicalResearch.com Interview with:
Michael A. Postow, MD
Louis V. Gerstner, Jr. Graduate School of Biomedical Sciences (GSK)
Memorial Sloan Kettering
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Postow: Pembrolizumab has been shown to improve overall survival for patients with advanced melanoma compared to ipilimumab. Patients with PD-L1 negative tumors still respond to pembrolizumab. Responses to pembrolizumab were higher when patients had more PD-L1 in the tumor.
MedicalResearch.com: What should clinicians and patients take away from your report?
Dr. Postow: PD-L1 status cannot be used to select patients with melanoma to receive pembrolizumab vs. ipilimumab or even to be used to determine eligibility for immunotherapy in general. PD-L1 “positivity” is a difficult definition and various cutoff points have been used in various studies to determine positivity. We need more research to determine the significance of various cutoff definitions of “positive.”
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Postow: We need to study additional immunologic biomarkers, in addition to PD-L1, to see if they can improve our understanding of who responds to immunotherapy and why.