# OnCo record trak-er (trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)". Whole corpus: https://onco.cc/api/v1/onco.nt
@prefix schema: <https://schema.org/> .
@prefix onco: <https://onco.cc/ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://onco.cc/trials/trak-er/>
  a schema:MedicalTrial ;
  onco:kind "trial" ;
  schema:identifier "trak-er", "NCT04985266" ;
  schema:name "TRAK-ER"@en ;
  schema:alternateName "TRAK ER"@en ;
  schema:description "A UK-led trial that tests the blood of women with high-risk hormone-receptor-positive breast cancer every three months, and offers a change of treatment to those whose blood turns positive before scans show anything."@en ;
  schema:url <https://onco.cc/trials/trak-er/> ;
  schema:dateModified "2026-11-04"^^xsd:date ;
  schema:citation <https://clinicaltrials.gov/study/NCT04985266>, <https://doi.org/10.1016/j.annonc.2026.10.1292> ;
  onco:status "recruiting" ;
  onco:phase "2" ;
  schema:startDate "2022-03-30" ;
  onco:related <https://onco.cc/trials/c-trak-tn/>, <https://onco.cc/trials/treat-ctdna/> ;
  onco:cancers <https://onco.cc/cancers/breast-hr-positive/> ;
  onco:technologies <https://onco.cc/technologies/mrd-testing/> ;
  onco:targets <https://onco.cc/targets/estrogen-receptor/> ;
  onco:drugs <https://onco.cc/drugs/palbociclib/>, <https://onco.cc/drugs/fulvestrant/>, <https://onco.cc/drugs/tamoxifen/>, <https://onco.cc/drugs/letrozole/>, <https://onco.cc/drugs/anastrozole/>, <https://onco.cc/drugs/exemestane/> ;
  onco:companies <https://onco.cc/companies/labcorp/>, <https://onco.cc/companies/invitae/> ;
  onco:institutions <https://onco.cc/institutions/royal-marsden/> ;
  onco:terms <https://onco.cc/terms/mrd/>, <https://onco.cc/terms/ctdna/>, <https://onco.cc/terms/tumour-informed-assay/> ;
  onco:bottlenecks <https://onco.cc/bottlenecks/b-subclone-attribution-residual-disease/> ;
  onco:keyPapers <https://onco.cc/key-papers/paper-cunningham-trak-er-surveillance-ann-oncol-2026/> .