{"entity":{"id":"persevera","kind":"trial","name":"persevERA","aka":[],"tldr":"An oral SERD did not beat the aromatase inhibitor in first-line treatment when both were combined with palbociclib. Oral SERDs earn their place after resistance, not before it.","summary":"persevERA, trial NCT04546009 sponsored by Roche and Genentech and reported in 2026, found that the oral SERD giredestrant did not beat letrozole in first-line treatment of ER-positive, HER2-negative advanced breast cancer when both were combined with palbociclib, suggesting oral SERDs earn their place after resistance rather than before it. It randomised 978 women, and its primary endpoint of investigator-assessed progression-free survival was not met, as announced on 9 March 2026 and presented at ASCO 2026, with a numerical improvement of about eleven percent that was not significant. OnCo links it to giredestrant and palbociclib. Whether an ESR1-selected first-line strategy would fare differently is the open question.","status":"negative","asOf":"2026-09-07","links":[{"label":"ClinicalTrials.gov NCT04546009","url":"https://clinicaltrials.gov/study/NCT04546009"}],"tags":["failure","lesson:selection"],"related":[],"cancers":["breast-hr-positive"],"sections":[],"technologies":["endocrine-therapy"],"targets":[],"drugs":["giredestrant","palbociclib"],"companies":["roche-genentech"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT04546009","phase":"3","setting":"First-line ER+/HER2- advanced breast cancer: giredestrant + palbociclib vs letrozole + palbociclib","sponsor":"Roche / Genentech","result":"PFS 33.1 vs 28.2 months, not significant.","started":"2020-10-09","startedType":"actual","yearReported":2026,"enrolled":992,"enrolledBasis":"registry","outcomes":[{"endpoint":"Progression-free survival (investigator)","primary":true,"unit":"months","arms":[{"name":"Giredestrant + palbociclib","value":33.1},{"name":"Letrozole + palbociclib","value":28.2}],"source":"https://www.roche.com/media/releases/med-cor-2026-03-09"}],"replication":"Consistent with the null result of first-line oral SERD strategies without ESR1 selection (e.g., SERENA-4 pending); contrasts with the adjuvant lidERA success."},"route":"/trials/persevera/","neighbours":{"cancer":[{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"}],"technology":[{"id":"endocrine-therapy","kind":"technology","name":"Endocrine therapy (SERMs, AIs, SERDs)","route":"/technologies/endocrine-therapy/"}],"drug":[{"id":"giredestrant","kind":"drug","name":"Giredestrant","route":"/drugs/giredestrant/"},{"id":"palbociclib","kind":"drug","name":"Palbociclib","route":"/drugs/palbociclib/"}],"company":[{"id":"roche-genentech","kind":"company","name":"Roche / Genentech","route":"/companies/roche-genentech/"}],"roadmap":[{"id":"hormonal-therapy-roadmap","kind":"roadmap","name":"Hormonal therapy roadmap: removing the ovaries → tamoxifen → oral degraders switched by a blood test","route":"/roadmaps/hormonal-therapy-roadmap/"}]}}