Table of Contents
Definition / general | Trade name | Indications | Uses by pathologists | Board review style question #1 | Board review style answer #1Cite this page: Kwee HG. Durvalumab. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/drugsgdurvalumab.html. Accessed January 22nd, 2021.
Definition / general
- Human IgG1 kappa monoclonal antibody that blocks the interaction of PDL1 with PD1 and CD80
- PDL1 blocks T cell function through interaction with PD1 and CD80
- Blockade of PDL1 by durvalumab releases the inhibition of immune responses without inducing antibody dependent cell mediated cytotoxicity
- Astra Zeneca: Imfinzi product insert [Accessed 14 December 2018]
Trade name
- Imfinzi®
Indications
- Locally advanced or metastatic urothelial carcinomas that have:
- Progression during or after platinum containing chemotherapy or
- Progression within 12 months of neoadjuvant or adjuvant treatment with platinum containing chemotherapy
- Unresectable stage III non small cell lung cancer that has not progressed following concurrent platinum based chemotherapy and radiation therapy (Astra Zeneca: Imfinzi product insert [Accessed 14 December 2018])
Uses by pathologists
- FDA has approved a companion test: Ventana PDL1 (SP263) immunohistochemistry assay using a rabbit monoclonal anti-PDL1 clone 263 to assess PDL1 protein in FFPE urothelial carcinoma tissue stained with OptiView DAB IHC detection kit on a Ventana BenchMark Ultra instrument
- Scoring method:
- Determine the percentage of tumor cells with any membranous staining above background or
- Percentage of tumor associated immune cells with staining at any intensity above background (IC+) or
- Percentage of tumor area occupied by tumor associated immune cells (ICP)
- PDL1 status is high if any of these conditions are met:
- At least 25% of tumor cells show membranous staining or
- ICP is greater than 1% and IC+ is at least 25% or
- ICP is at least 1% and IC+ is 100%
- This test is a useful tool to help determine the likelihood of the urothelial carcinoma responding to durvalumab, but it is not required for the use of durvalumab
- For nonsmall cell lung cancer the cutoff criteria is at least 25% of tumor cells with membranous staining (Arch Pathol Lab Med 2018;142:26)
- A blueprint project to evaluate the comparability of the various PDL1 assays (including SP263) had been published (J Thorac Oncol 2017;12:208)
Board review style question #1
- Which of the following factors is not part of the assessment of PDL1 status of urothelial carcinoma using the Ventana PDL1 (SP263) antibody:
- Percentage of tumor area occupied by tumor associated immune cells
- Percentage of tumor cells with membranous staining
- Percentage of tumor cells with nuclear staining
- Percentage of tumor-associated immune cells with positive staining
Board review style answer #1