{"entity":{"id":"ventana-mmr-rxdx","kind":"drug","name":"VENTANA MMR RxDx Panel","aka":[],"tldr":"A four-stain test that shows whether a womb cancer has lost its DNA spell-checker, which makes immunotherapy likely to work.","summary":"Approved by the FDA in August 2021 together with dostarlimab for mismatch-repair-deficient (dMMR) recurrent or advanced endometrial cancer, the first immunohistochemistry companion diagnostic for mismatch-repair status. MMR immunohistochemistry is cheap, fast and available in every pathology laboratory, and is the recommended first-line test in endometrial and colorectal cancer, where it also serves as universal screening for Lynch syndrome. Where results are equivocal, PCR or NGS-based microsatellite-instability testing is used. Immunotherapy responses in dMMR tumours are among the most durable in oncology, so the stain has outsized consequences for a patient.","status":"approved","asOf":"2026-09-10","links":[{"label":"FDA: dostarlimab accelerated approval (dMMR endometrial cancer) (archived copy)","url":"https://web.archive.org/web/20260217063458/https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-dostarlimab-gxly-dmmr-endometrial-cancer"}],"tags":["test"],"related":[],"cancers":["endometrial","colorectal","pancreatic"],"sections":[],"technologies":["msi-mmr-testing","companion-diagnostic","histopathology-ihc"],"targets":[],"drugs":["dostarlimab","pembrolizumab"],"companies":["roche-genentech"],"institutions":[],"pathways":[],"terms":["msi","mss-pmmr","lynch-syndrome","endometrial-molecular-classes"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-luchini-msi-dmmr-pancreatic-systematic-review-gut-2021","paper-moreira-lynch-syndrome-identification-jama-2012","paper-sepulveda-molecular-biomarkers-colorectal-guideline-jco-2017"],"journals":[],"dependsOn":[],"notes":["What a result means: loss of one or more MMR proteins (dMMR) means checkpoint immunotherapy is an option and that inherited Lynch syndrome should be considered; intact staining (pMMR) means other treatments come first.","Colorectal cancer: the four-protein mismatch repair immunohistochemistry panel is the guideline-recommended first test on every colorectal cancer, both to find Lynch syndrome and to select immunotherapy (Moreira 2012, Sepulveda 2017)."],"brand":"VENTANA MMR RxDx","modality":"Mismatch-repair immunohistochemistry companion diagnostic assay","mechanism":"Four immunohistochemical stains (MLH1, PMS2, MSH2, MSH6) read together; loss of nuclear staining for any protein classifies the tumour as mismatch-repair deficient.","approvals":[{"region":"US","year":2021,"indication":"Companion diagnostic for dostarlimab in dMMR endometrial cancer"}],"mechanismSteps":[],"toxicity":[],"access":[],"regulatoryEvents":[]},"route":"/drugs/ventana-mmr-rxdx/","neighbours":{"cancer":[{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"endometrial","kind":"cancer","name":"Endometrial cancer","route":"/cancers/endometrial/"},{"id":"gallbladder","kind":"cancer","name":"Gallbladder cancer","route":"/cancers/gallbladder/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"technology":[{"id":"companion-diagnostic","kind":"technology","name":"Companion diagnostics","route":"/technologies/companion-diagnostic/"},{"id":"histopathology-ihc","kind":"technology","name":"Histopathology & immunohistochemistry","route":"/technologies/histopathology-ihc/"},{"id":"msi-mmr-testing","kind":"technology","name":"MSI and mismatch-repair testing","route":"/technologies/msi-mmr-testing/"}],"drug":[{"id":"dostarlimab","kind":"drug","name":"Dostarlimab","route":"/drugs/dostarlimab/"},{"id":"pembrolizumab","kind":"drug","name":"Pembrolizumab","route":"/drugs/pembrolizumab/"}],"company":[{"id":"roche-genentech","kind":"company","name":"Roche / Genentech","route":"/companies/roche-genentech/"}],"term":[{"id":"endometrial-molecular-classes","kind":"term","name":"Endometrial cancer molecular classes (POLEmut, MMRd, p53abn, NSMP)","route":"/terms/endometrial-molecular-classes/"},{"id":"lynch-syndrome","kind":"term","name":"Lynch syndrome","route":"/terms/lynch-syndrome/"},{"id":"msi","kind":"term","name":"Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR)","route":"/terms/msi/"},{"id":"mss-pmmr","kind":"term","name":"Microsatellite-stable (MSS) / mismatch-repair proficient (pMMR)","route":"/terms/mss-pmmr/"}],"paper":[{"id":"paper-luchini-msi-dmmr-pancreatic-systematic-review-gut-2021","kind":"paper","name":"Comprehensive characterisation of pancreatic ductal adenocarcinoma with microsatellite instability: histology, molecular pathology and clinical implications","route":"/key-papers/paper-luchini-msi-dmmr-pancreatic-systematic-review-gut-2021/"},{"id":"paper-moreira-lynch-syndrome-identification-jama-2012","kind":"paper","name":"Identification of Lynch syndrome among patients with colorectal cancer","route":"/key-papers/paper-moreira-lynch-syndrome-identification-jama-2012/"},{"id":"paper-sepulveda-molecular-biomarkers-colorectal-guideline-jco-2017","kind":"paper","name":"Molecular biomarkers for the evaluation of colorectal cancer: guideline from ASCP, CAP, AMP and ASCO","route":"/key-papers/paper-sepulveda-molecular-biomarkers-colorectal-guideline-jco-2017/"}],"biomarker":[{"id":"dmmr-ihc","kind":"biomarker","name":"dMMR (mismatch repair deficiency by IHC)","route":"/biomarkers/dmmr-ihc/"}],"target":[{"id":"mlh1","kind":"target","name":"MLH1","route":"/targets/mlh1/"},{"id":"msh2","kind":"target","name":"MSH2","route":"/targets/msh2/"},{"id":"msh6","kind":"target","name":"MSH6","route":"/targets/msh6/"},{"id":"pms2","kind":"target","name":"PMS2","route":"/targets/pms2/"}]}}