Matt Oberley
Executive Medical Director
MI EXOME™ (WES), an NGS-based Assay
Caris Life Sciences® has recently launched MI Exome™ (WES), a next-generation sequencing-based assay analyzing all 22,000 coding DNA genes in the human genome, which replaces our 592 gene DNA sequencing assay. The analysis of data from WES detects clinically actionable DNA point mutations, insertions/deletions, and copy number alterations. WES also includes genomic signatures such as Tumor Mutational Burden (TMB), Microsatellite Instability (MSI), Loss of Heterozygosity (LOH), and plans are underway to validate Homologous Recombination Deficiency (HRD) scoring. Additionally, sequencing of cancer-related pathogens will be included as part of the WES testing (including viral, bacterial, and fungal pathogens). The WES testing will complement whole transcriptome sequencing (MI Transcriptome™; WTS), to provide an unmatched evaluation of the cancer genome for a more refined treatment selection where properly indicated. In April 2020, Caris submitted the MI Exome Pre-Market Approval (PMA) for review to the FDA to include key companion diagnostic (CDx) biomarkers and claims for MI Exome CDx, with an estimated approval in early 2021.
This unique Caris approach allows MI Exome to cover an expansive amount of the genome, without sacrificing our market leading turn-around time. We are able to modulate the depth of coverage by using proprietary proportions of bait panels. MI Exome will cover 720 core clinically actionably or known oncogenic genes at a 500x depth of sequencing. This maintains the robust sensitivity needed to ensure detection of mutations that drive FDA approved therapies or to drive enrolment into clinical trials, even with limited tumor tissue. The remaining exome will be balance covered at depth of 200x. In addition, MI Exome sequences 250,000 evenly-spaced (approximately 17 per megabase) exonic, intronic, and intergenic single nucleotide polymorphisms (SNP) to enhance detection of genome-level alterations, gene gain/loss and genome-wide instability. This gives an ability to detect copy number alterations and LOH events with sub-megabase resolution.
The most exciting part about the launch of WES for me is that it means that Caris is able to offer the most comprehensive DNA and RNA analyses for each and every patient. Robust molecular information to help cancer patients fight their disease is what drives us and inspires us to keep innovating.