{"entity":{"id":"hrd-positive","kind":"biomarker","name":"HRD-positive (genomic instability score)","aka":["HRD","HRD-positive","HRD positive","homologous recombination deficiency","genomic instability score","GIS","GIS >= 42","myChoice HRD","HRD score","genomic scar"],"tldr":"HRD-positive means the tumour's genome carries the scars of failed double-strand break repair (or a BRCA mutation), measured as a genomic instability score. In ovarian cancer it selects niraparib, and olaparib with bevacizumab, as first-line maintenance.","summary":"The Myriad myChoice CDx combines tumour BRCA1/2 status with a genomic instability score built from loss of heterozygosity, telomeric allelic imbalance and large-scale state transitions; the assay calls HRD-positive at a GIS of 42 or more (the PRIMA and PAOLA-1 trials' cut-off) or any deleterious BRCA mutation. Niraparib's US label defines HRD-positive status as 'a deleterious or suspected deleterious BRCA mutation, and/or genomic instability' and the olaparib plus bevacizumab first-line maintenance indication is for HRD-positive advanced ovarian cancer. Because the scar accumulates over time, HRD status is read on tumour tissue and does not capture reversion, which is why HRD-positive tumours can still be PARP-resistant.","asOf":"2026-09-23","links":[{"label":"ZEJULA prescribing information (DailyMed)","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b7f675e2-159c-490c-b6f4-3f16d9492b7d"},{"label":"Lynparza prescribing information (DailyMed)","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=741ff3e3-dc1a-45a6-84e5-2481b27131aa"}],"tags":["biomarker","brca","genome-wide"],"related":["brca-somatic","brca-germline"],"cancers":["ovarian","high-grade-serous-ovarian-cancer"],"sections":[],"technologies":[],"targets":[],"drugs":["niraparib","olaparib","bevacizumab","mychoice-cdx"],"companies":[],"institutions":[],"pathways":[],"terms":["hrd","platinum-sensitivity"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"target":"brca","measurement":"genomic-instability-score","scoringRule":{"text":"HRD-positive: a deleterious or suspected deleterious tumour BRCA1/2 mutation, or a genomic instability score at or above the assay's cut-off (42 on the myChoice CDx), computed from loss of heterozygosity, telomeric allelic imbalance and large-scale state transitions.","quote":"Deleterious or suspected deleterious germline or somatic mutations in BRCA1 and BRCA2 genes and/or positive Genomic Instability Score","source":"https://www.fda.gov/medical-devices/in-vitro-diagnostics/list-cleared-or-approved-companion-diagnostic-devices-in-vitro-and-imaging-tools","sourceLabel":"FDA: List of FDA-Authorized Companion Diagnostic Devices"},"thresholds":[{"value":"HRD-positive (BRCA mutation and/or genomic instability)","drugId":"niraparib","cancerId":"ovarian","regulator":"FDA","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b7f675e2-159c-490c-b6f4-3f16d9492b7d","quote":"for the maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to first-line platinum-based chemotherapy and whose cancer is associated with homologous recombination deficiency (HRD)-positive status defined by either: o a deleterious or suspected deleterious BRCA mutation, and/or o genomic instability","status":"current"},{"value":"HRD-positive","drugId":"olaparib","cancerId":"ovarian","regulator":"FDA","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=741ff3e3-dc1a-45a6-84e5-2481b27131aa","quote":"First-line Maintenance Treatment of HRD-positive Advanced Ovarian Cancer in Combination with Bevacizumab Lynparza is indicated in combination with bevacizumab for the maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube or primary peritoneal cancer who are in complete or partial response to first-line platinum-based chemotherapy","status":"current"}],"tests":["mychoice-cdx","caris-mi-profile","tempus-xt"],"assays":["mychoice-cdx"],"companionDiagnostics":[{"device":"Myriad myChoice CDx","maker":"Myriad Genetic Laboratories","companyId":"myriad-genetics","drugs":["olaparib"],"indication":"Ovarian Cancer - Tissue","pma":"P190014/S003 (05/08/2020)","source":"https://www.fda.gov/medical-devices/in-vitro-diagnostics/list-cleared-or-approved-companion-diagnostic-devices-in-vitro-and-imaging-tools"},{"device":"Myriad myChoice CDx","maker":"Myriad Genetic Laboratories","companyId":"myriad-genetics","drugs":["niraparib"],"indication":"Ovarian Cancer - Tissue","pma":"P190014/S011 (03/10/2026)","source":"https://www.fda.gov/medical-devices/in-vitro-diagnostics/list-cleared-or-approved-companion-diagnostic-devices-in-vitro-and-imaging-tools"}],"forPatient":"HRD-positive on a myChoice report (a BRCA mutation or a genomic instability score of 42 or more) means your ovarian cancer is likely to respond to PARP inhibitors: niraparib alone, or olaparib with bevacizumab, are on label as maintenance after first chemotherapy. An HRD-negative result does not rule out niraparib, whose first-line label covers all comers, but the expected benefit is smaller."},"route":"/biomarkers/hrd-positive/","neighbours":{"biomarker":[{"id":"folr1-expression","kind":"biomarker","name":"Folate receptor alpha expression (FRα-positive, PS2+ >= 75%)","route":"/biomarkers/folr1-expression/"},{"id":"brca-germline","kind":"biomarker","name":"Germline BRCA1/2 pathogenic variant (gBRCAm)","route":"/biomarkers/brca-germline/"},{"id":"brca-somatic","kind":"biomarker","name":"Tumour (somatic or germline) BRCA1/2 mutation and HRR gene alterations","route":"/biomarkers/brca-somatic/"}],"cancer":[{"id":"high-grade-serous-ovarian-cancer","kind":"cancer","name":"High-grade serous ovarian cancer","route":"/cancers/high-grade-serous-ovarian-cancer/"},{"id":"ovarian","kind":"cancer","name":"Ovarian cancer","route":"/cancers/ovarian/"}],"drug":[{"id":"bevacizumab","kind":"drug","name":"Bevacizumab","route":"/drugs/bevacizumab/"},{"id":"mychoice-cdx","kind":"drug","name":"myChoice CDx","route":"/drugs/mychoice-cdx/"},{"id":"niraparib","kind":"drug","name":"Niraparib","route":"/drugs/niraparib/"},{"id":"olaparib","kind":"drug","name":"Olaparib","route":"/drugs/olaparib/"}],"term":[{"id":"hrd","kind":"term","name":"Homologous recombination deficiency (HRD)","route":"/terms/hrd/"},{"id":"platinum-sensitivity","kind":"term","name":"Platinum-sensitive / platinum-resistant","route":"/terms/platinum-sensitivity/"}],"target":[{"id":"brca","kind":"target","name":"BRCA1 / BRCA2 (HRD)","route":"/targets/brca/"}]}}