Abstract 3614
Background
The clinical utility of non-invasive liquid biopsy and ability to accurately detect EGFR mutations in circulating-tumor DNA of patients with NSCLC has been well demonstrated. This expands the pool of patients eligible for molecular testing. The cobas® EGFR Mutation Test v2 (cobas test) is a real-time PCR test for qualitative and semi-quantitative detection of 42 EGFR mutations in DNA from tissue and circulating free DNA (cfDNA) from K2 EDTA plasma. Blood collected in K2 EDTA requires plasma be separated within 8 hours, which can be a barrier to molecular testing and thus impact treatment decisions. The Roche Cell-Free DNA Collection Tube (Roche cfDNA) stabilizes blood up to 8 days, allowing greater flexibility in transportation and time to plasma separation. Here the suitability of plasma from Roche cfDNA tubes for use with the cobas test is demonstrated.
Methods
Test performance with Roche cfDNA plasma was verified with NSCLC patient specimens or surrogate samples (sheared cell line DNA in healthy donor plasma). Correlation was tested using paired draws in K2 EDTA and Roche cfDNA tubes for 51 NSCLC patients and 20 healthy donor surrogate samples. Limit of detection (LoD) and linearity established with K2 EDTA plasma were verified with Roche cfDNA plasma. Reproducibility was assessed using surrogate samples at two levels with multiple operators, Roche cfDNA tube lots, instruments, days and sites. Blood storage conditions were established at an external laboratory with 6 NSCLC patient specimens.
Results
Compared to K2 EDTA plasma, Roche cfDNA plasma had a PPA, NPA and OPA of 100.0% with the cobas test. LoD for EGFR mutation detection in Roche cfDNA plasma was verified as ≤ 100 cp/mL. Linearity for EGFR mutations in Roche cfDNA plasma was verified. The reproducibility study had a call agreement of ≥ 98.6%. Blood in Roche cfDNA tubes was stable for up to 8 days at 18-25ºC with one excursion of up to 24 hours at 15-30ºC prior to separation.
Conclusions
Use of the Roche cfDNA tube with the cobas® EGFR Mutation Test v2 provides the flexibility to store blood for up to 8 days prior to separation, with equivalent performance to K2 EDTA plasma, and facilitates use of liquid biopsy for NSCLC patients needing molecular testing.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Roche Molecular Systems Inc.
Funding
AstraZeneca PLC.
Disclosure
T.E. May: Full / Part-time employment: Roche Molecular Solutions. S.A. Scudder: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche Molecular Solutions. S.J. Joshi: Full / Part-time employment: Roche Molecular Solutions. M. Kohlmann: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca, PLC. N. Shrestha: Full / Part-time employment: Roche Molecular Solutions. N. Lee: Full / Part-time employment: Roche Molecular Solutions. J. Lai: Full / Part-time employment: Roche Molecular Systems Inc. M. Tsourounis: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca PLC. A. Kohlmann: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca PLC. P. O’Donnell: Full / Part-time employment, Spouse / Financial dependant: Roche Molecular Systems. H. Halait: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche Molecular Systems. All other authors have declared no conflicts of interest.
Resources from the same session
4614 - Predictors of Response to Checkpoint Inhibitors in Naïve and Ipilimumab-Refractory Melanoma
Presenter: Domenico Mallardo
Session: Poster Display session 3
Resources:
Abstract
2901 - IFN-γ/IL-10 ratio as predictive biomarker for response to anti-PD-1 therapy in metastatic melanoma patients
Presenter: Emilio Giunta
Session: Poster Display session 3
Resources:
Abstract
2306 - Multiplex Chromogenic Immunohistochemistry (IHC) for Spatial Analysis of Checkpoint-Positive Tumor Infiltrating Lymphocytes (TILs)
Presenter: Scott Ely
Session: Poster Display session 3
Resources:
Abstract
1678 - The role of PD-L1 expression as a predictive biomarker in advanced renal cell carcinoma: a meta-analysis of randomized clinical trials.
Presenter: Alberto Carretero-Gonzalez
Session: Poster Display session 3
Resources:
Abstract
5138 - Radiomic Features as a Non-invasive Biomarker to Predict Response to Immunotherapy in Recurrent or Metastatic Urothelial Carcinoma
Presenter: Kye Jin Park
Session: Poster Display session 3
Resources:
Abstract
5800 - Integrative combination of high-plex digital profiling techniques and cluster analysis to reveal complex immune biology in the tumor microenvironment of mesothelioma
Presenter: Carmen Ballesteros-Merino
Session: Poster Display session 3
Resources:
Abstract
5736 - Predictive factors of response to immunotherapy in 198 patients with metastatic non-microcytic lung cancer (mNSCLC): real world data from 2 university hospitals in Spain
Presenter: Juan Felipe Cordoba Ortega
Session: Poster Display session 3
Resources:
Abstract
5645 - Evaluating Lung CT Density Changes Among Patients with Extensive Stage Small Cell Lung Cancer (ES-SCLC) Treated with Thoracic Radiotherapy (TRT) alone or TRT Followed by Combined Ipilimumab (IPI) and Nivolumab (NIVO).
Presenter: Kujtim Latifi
Session: Poster Display session 3
Resources:
Abstract
1540 - Immuno-oncology therapy biomarkers differences between polyoma-virus positive and negative Merkel cell carcinomas
Presenter: Zoran Gatalica
Session: Poster Display session 3
Resources:
Abstract
4538 - Can we improve patient selection for phase 1 clinical trials (Ph1) based on Immuno-Oncology score prognostic index (VIO)?
Presenter: Ignacio Matos Garcia
Session: Poster Display session 3
Resources:
Abstract