Dilemma of scoring PD-L1 by Immunohistochemistry

Dr. Shiv Kumar Chabba; Dr. Sagarika Sarkar; Dr. Anil Malleshi Betigeri

Volume : VII, Issue : III, March - 2018

Dilemma of scoring PD-L1 by Immunohistochemistry

Dr. Shiv Kumar Chabba, Dr. Sagarika Sarkar, Dr. Anil Malleshi Betigeri

Abstract :

Cancer therapeutics have evolved with the advent of newer drugs that target immune inhibitory checkpoints. Pemolizumab and Nivolumab are FDA approved drugs with different diagnostic guidelines. Pemolizumab, requires a companion diagnostic test PD– L1 immunohistochemistry (IHC) 22C3 pharmDx test, in non–small cell lung tumours. The FDA has acknowledged that the level of PD–L1 IHC expression may help to identify patients who are likely to have improved survival due to treatment with Nivolumab by approving a corresponding test. PD–L1 IHC test is being used as a “complementary diagnostic test” for Nivolumab. In future approvals for other similar anti–PD–L1 agents, such as Atezolizumab (Roche/Genentech, Basel, Switzerland), Durvalumab (Astra Zeneca, Camidge, United Kingdom), and Avelumab (Pfizer/Merck Serono, Berlin/Darmstadt, Germany), may be anticipated. This article is an attempt to address present issues associated with PD–L1 by IHC method.