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The National Cancer Institute–Molecular Analysis for Therapy Choice (NCI-MATCH) trial is a national signal-finding precision medicine study that relies on genomic assays to screen and enroll patients with relapsed or refractory cancer after standard treatments. We report the analytical validation processes for the next-generation sequencing (NGS) assay that was tailored for regulatory compliant use in the trial. The Oncomine Cancer Panel assay and the Personal Genome Machine were used in four networked laboratories accredited for the Clinical Laboratory Improvement Amendments. Using formalin-fixed paraffin-embedded clinical specimens and cell lines, we found that the assay achieved overall sensitivity of 96.98% for 265 known mutations and 99.99% specificity. High reproducibility in detecting all reportable variants was observed, with a 99.99% mean interoperator pairwise concordance across the four laboratories. The limit of detection for each variant type was 2.8% for single-nucleotide variants, 10.5% for insertion/deletions, 6.8% for large insertion/deletions (gap ≥4 bp), and four copies for gene amplification. The assay system from biopsy collection through reporting was tested and found to be fully fit for purpose. Our results indicate that the NCI-MATCH NGS assay met the criteria for the intended clinical use and that high reproducibility of a complex NGS assay is achievable across multiple clinical laboratories. Our validation approaches can serve as a template for development and validation of other NGS assays for precision medicine.

Robust and analytically validated assays are essential for clinical studies. We outline an analytical validation study of a targeted next-generation sequencing mutation-detection assay used for patient selection in the National Cancer Institute Molecular Profiling–Based Assignment of Cancer Therapy (NCI-MPACT) trial (NCT01827384). Using DNA samples from normal or tumor cell lines and xenografts with known variants, we assessed the sensitivity, specificity, and reproducibility of the NCI-MPACT assay in five variant types: single-nucleotide variants (SNVs), SNVs at homopolymeric (HP) regions (≥3 identical bases), small insertions/deletions (indels), large indels (gap ≥4 bp), and indels at HP regions. The assay achieved sensitivities of 100% for 64 SNVs, nine SNVs at HP regions, and 11 large indels, 83.33% for six indels, and 93.33% for 15 indels at HP regions. Zero false positives (100% specificity) were found in 380 actionable mutation loci in 96 runs of haplotype map cells. Reproducibility analysis showed 96.3% to 100% intraoperator and 98.1% to 100% interoperator mean concordance in detected variants and 100% reproducibility in treatment selection. To date, 38 tumors have been screened, 34 passed preanalytical quality control, and 18 had actionable mutations for treatment assignment. The NCI-MPACT assay is well suited for its intended investigational use and can serve as a template for developing next-generation sequencing assays for other cancer clinical trial applications.

3016 Background: NCI-MATCH is a precision medicine trial that assigns treatment to refractory cancer patients by tumor mutation profile rather than by histology. After screening fresh tumor biopsies from nearly 6000 patients many treatment arms did not meet accrual due to the low prevalence of the eligible variants. NCI MATCH developed an approach to identify patients for the remaining arms utilizing a network of academic and commercial CLIA-certified labs that perform NGS assays as routine care at MATCH participating sites. Methods: Candidate labs were recruited through a notice in the Federal Register and posted on the NCI and ECOG ACRIN web sites. Twenty-seven labs (17 academic/10 commercial) submitted applications. After acceptance each lab analyzed a common set of 10 DNAs extracted from 8 cell lines and 2 clinical samples for concordance with the central NCI-MATCH NGS assay. Results: For the 17 labs with concordance results, a median of 8 (range 2 – 58) copy number variants (CNVs) were evaluated by the NGS assay of each DL, with the number evaluated depending on each lab’s clinical assay panel content. CNV concordance between central and DL assays, as measured by positive percent agreement (PPA), averaged 98.7% (range 87.5% - 100%) with the central assay as referent and 94.1% (range 77.8% – 100%) with the DL assay as referent. For single nucleotide variants (SNVs) and Insertion/deletions (Indels) combined, a median of 19 variants (range 11 – 26) were evaluated by each DL for concordance. PPA between central and DL assays averaged 98.0% (range 87.5% – 100%) and 98.6% (range 90.0% – 100%) with central and DL assay as referents, respectively. Strong correlations were observed between central and DL assays for both CNVs (median r = 0.93; 0.33 – 1.00) and SNV/Indels (median r = 0.98; 0.67 – 0.99). Conclusions: Our results suggest that different NGS assay platforms using diverse strategies for target enrichment and data analysis may still achieve high concordance if pre-analytical variables are minimized and the common genomic regions interrogated by each assay are well-understood. The designated lab network allows for a wider search for rare variants in tumors and provides a model for conducting future clinical trials. Clinical trial information: NCT02465060.

The National Cancer Institute-Molecular Analysis for Therapy Choice (NCI-MATCH) trial is a national signal-finding precision medicine study that relies on genomic assays to screen and enroll patients with relapsed or refractory cancer after standard treatments. We report the analytical validation processes for the next-generation sequencing (NGS) assay that was tailored for regulatory compliant use in the trial. The Oncomine Cancer Panel assay and the Personal Genome Machine were used in four networked laboratories accredited for the Clinical Laboratory Improvement Amendments. Using formalin-fixed paraffin-embedded clinical specimens and cell lines, we found that the assay achieved overall sensitivity of 96.98% for 265 known mutations and 99.99% specificity. High reproducibility in detecting all reportable variants was observed, with a 99.99% mean interoperator pairwise concordance across the four laboratories. The limit of detection for each variant type was 2.8% for single-nucleotide variants, 10.5% for insertion/deletions, 6.8% for large insertion/deletions (gap ≥4 bp), and four copies for gene amplification. The assay system from biopsy collection through reporting was tested and found to be fully fit for purpose. Our results indicate that the NCI-MATCH NGS assay met the criteria for the intended clinical use and that high reproducibility of a complex NGS assay is achievable across multiple clinical laboratories. Our validation approaches can serve as a template for development and validation of other NGS assays for precision medicine.

Although next-generation sequencing technologies have been widely adapted for clinical diagnostic applications, an urgent need exists for multianalyte calibrator materials and controls to evaluate the performance of these assays. Control materials will also play a major role in the assessment, development, and selection of appropriate alignment and variant calling pipelines. We report an approach to provide effective multianalyte controls for next-generation sequencing assays, referred to as the control plasmid spiked-in genome (CPSG). Control plasmids that contain approximately 1000 bases of human genomic sequence with a specific mutation of interest positioned near the middle of the insert and a nearby 6-bp molecular barcode were synthesized, linearized, quantitated, and spiked into genomic DNA derived from formalin-fixed, paraffin-embedded–prepared hapmap cell lines at defined copy number ratios. Serial titration experiments demonstrated the CPSGs performed with similar efficiency of variant detection as formalin-fixed, paraffin-embedded cell line genomic DNA. Repetitive analyses of one lot of CPSGs 90 times during 18 months revealed that the reagents were stable with consistent detection of each of the plasmids at similar variant allele frequencies. CPSGs are designed to work across most next-generation sequencing methods, platforms, and data analysis pipelines. CPSGs are robust controls and can be used to evaluate the performance of different next-generation sequencing diagnostic assays, assess data analysis pipelines, and ensure robust assay performance metrics.

The National Institute of Standards and Technology (NIST) Standard Reference Materials 2373 is a set of genomic DNA samples prepared from five breast cancer cell lines with certified values for the ratio of the HER2 gene copy number to the copy numbers of reference genes determined by real-time quantitative PCR and digital PCR. Targeted-amplicon, whole-exome, and whole-genome sequencing measurements were used with the reference material to compare the performance of both the laboratory steps and the bioinformatic approaches of the different methods using a range of amplification ratios. Although good reproducibility was observed in each next-generation sequencing method, slightly different HER2 copy numbers associated with platform-specific biases were obtained. This study clearly demonstrates the value of Standard Reference Materials 2373 as reference material and as a calibrator for evaluating assay performance as well as for increasing confidence in reporting HER2 amplification for clinical applications.