# OnCo record keynote-991 (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/keynote-991/>
  a schema:MedicalTrial ;
  onco:kind "trial" ;
  schema:identifier "keynote-991", "NCT04191096" ;
  schema:name "KEYNOTE-991"@en ;
  schema:alternateName "KEYNOTE-991"@en, "MK-3475-991"@en ;
  schema:description "The last attempt to make immunotherapy work in prostate cancer, this time as early as possible. It was stopped for futility and made rashes and serious side effects much commoner."@en ;
  schema:url <https://onco.cc/trials/keynote-991/> ;
  schema:dateModified "2026-09-25"^^xsd:date ;
  schema:citation <https://clinicaltrials.gov/study/NCT04191096>, <https://doi.org/10.1016/j.annonc.2025.05.008> ;
  onco:status "negative" ;
  onco:phase "3" ;
  onco:cancers <https://onco.cc/cancers/prostate/>, <https://onco.cc/cancers/prostate-mhspc/> ;
  onco:technologies <https://onco.cc/technologies/checkpoint-inhibitor/>, <https://onco.cc/technologies/androgen-deprivation/> ;
  onco:targets <https://onco.cc/targets/pd1/>, <https://onco.cc/targets/androgen-receptor/> ;
  onco:drugs <https://onco.cc/drugs/pembrolizumab/>, <https://onco.cc/drugs/enzalutamide/> ;
  onco:companies <https://onco.cc/companies/merck/> ;
  onco:terms <https://onco.cc/terms/mcrpc-mhspc/>, <https://onco.cc/terms/arpi/>, <https://onco.cc/terms/adt/> ;
  onco:trials <https://onco.cc/trials/keynote-641/>, <https://onco.cc/trials/keynote-921/>, <https://onco.cc/trials/imbassador250/>, <https://onco.cc/trials/arches/>, <https://onco.cc/trials/enzamet/> .