The G-CIMP score correlates with patient survival and provides a new tool for physicians as they plan the patient's treatment. This unique multiple DNA Methylation biomarker test, developed and validated by RCSL and commercialized and marketed by Castle Biosciences, Inc (Friendswood, TX), offers significant improvements in sensitivity, patient sample requirements and reproducibility over the bisulfite DNA methylation platform. These improvements were achieved by utilizing RiboMed's proprietary and patented bisulfite-free Abscription®-based MethylMeter® platform.
As noted by RiboMed CEO Dr. Michelle Hanna, "The unparalleled sensitivity, accuracy, and reproducibility offered by the Abscription®-based G-CIMP test, coupled with its ability to efficiently assess multiple methylation biomarkers in FFPE patient samples, makes this the best in class option for prognostic glioma testing. Furthermore, MethylMeter is directly applicable to the development of a broad range of new diagnostic, theranostic, and companion diagnostic DNA methylation based assays, particularly those utilizing FFPE samples." RCSL's clinical diagnostic assay pipeline includes tests for ovarian and lung cancers.
The G-CIMP biomarker panel was originally discovered and correlated to glioma patient survival by researchers at the MD Anderson Cancer Center (MDACC) and exclusively licensed to Castle Biosciences. After initial unsuccessful attempts at commercialization using traditional bisulfite-based methylation detection platforms, Castle Biosciences adopted RiboMed's platform based on its ability to assay biomarker DNA Methylation profiles efficiently in degraded DNA found in FFPE patient tumor samples. RiboMed subsequently developed a robust G-CIMP biomarker test that shows concordance with the MDACC clinical DNA Methylation data correlating CIMP Methylation status with patient survival times. RCSL is now performing this test as a service for Castle. Multiple studies have provided ample evidence of clinically significant inter-observer variation of the histological typing and grading of glioma. This variation is clinically significant as treatment plans are based upon grade. The purpose of the G-CIMP biomarker test is to provide objective information to improve grade-related prognosis. "When traditional bisulfite-based technologies were found to be unsuitable for this FFPE assay, RiboMed's bisulfite-free methylation detection platform effectively circumvented the problems associated with these traditional technologies enabling the rapid development of an accurate and reproducible FFPE glioma tumor assay" stated Castle Biosciences CEO Derek Maetzold. "We are very excited to partner with RiboMed in offering the DecisonDX G-CIMP test since it will significantly improve glioma tumor grading and become the standard of care for these patients."