{"entity":{"id":"phergain","kind":"trial","name":"PHERGain","aka":[],"tldr":"Using an early PET scan to spot responders let a third of women be cured of HER2-positive breast cancer without any chemotherapy.","summary":"PET responders after 2 cycles continued antibodies alone; those achieving pCR (37.9% of the arm) skipped chemotherapy entirely. 3-year iDFS 95.4% in the PET-adapted arm, meeting its co-primary endpoint. Discussed at ESMO Breast 2026 as the model for imaging-guided de-escalation; a phase 3 (PHERGain-2) is underway.","status":"positive","asOf":"2026-09-07","links":[{"label":"ClinicalTrials.gov NCT03161353","url":"https://clinicaltrials.gov/study/NCT03161353"}],"tags":[],"related":[],"cancers":["breast-her2-positive","her2-positive-early-breast-cancer"],"sections":[],"technologies":["fdg-pet"],"targets":[],"drugs":["trastuzumab","pertuzumab"],"companies":[],"institutions":[],"pathways":[],"terms":["pcr"],"trials":[],"people":["aleix-prat","javier-cortes"],"bottlenecks":[],"keyPapers":["paper-phergain-lancet-oncol-2021","paper-phergain-lancet-2024-update"],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT03161353","phase":"2","setting":"HER2+ early breast cancer: chemotherapy-free trastuzumab + pertuzumab with early 18F-FDG PET response assessment to decide whether chemotherapy is needed","sponsor":"MEDSIR","result":"3-year iDFS 95.4% in the PET-adapted arm; ~1 in 3 spared chemotherapy.","started":"2017-06-26","startedType":"actual","yearReported":2024,"enrolled":377,"enrolledBasis":"registry","outcomes":[{"endpoint":"3-year invasive disease-free survival (PET-adapted arm)","primary":true,"unit":"%","arms":[{"name":"PET-adapted HP ± chemotherapy","n":285,"value":95.4}],"source":"https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00054-0/fulltext"}],"replication":"Consistent with WSG-ADAPT HER2+/HR- (pCR-guided de-escalation); phase 3 confirmation pending."},"route":"/trials/phergain/","neighbours":{"cancer":[{"id":"her2-positive-early-breast-cancer","kind":"cancer","name":"Early HER2-positive breast cancer","route":"/cancers/her2-positive-early-breast-cancer/"},{"id":"breast-her2-positive","kind":"cancer","name":"HER2-positive breast cancer","route":"/cancers/breast-her2-positive/"}],"technology":[{"id":"fdg-pet","kind":"technology","name":"FDG PET","route":"/technologies/fdg-pet/"}],"drug":[{"id":"pertuzumab","kind":"drug","name":"Pertuzumab","route":"/drugs/pertuzumab/"},{"id":"trastuzumab","kind":"drug","name":"Trastuzumab","route":"/drugs/trastuzumab/"}],"term":[{"id":"pcr","kind":"term","name":"Pathologic complete response (pCR)","route":"/terms/pcr/"}],"person":[{"id":"aleix-prat","kind":"person","name":"Aleix Prat","route":"/people/aleix-prat/"},{"id":"javier-cortes","kind":"person","name":"Javier Cortés","route":"/people/javier-cortes/"}],"paper":[{"id":"paper-phergain-lancet-2024-update","kind":"paper","name":"3-year invasive disease-free survival with chemotherapy de-escalation using an 18 F-FDG-PET-based, pathological complete response-adapted strategy in HER2-positive early breast cancer (PHERGain): a randomised, open-label, phase 2 trial","route":"/key-papers/paper-phergain-lancet-2024-update/"},{"id":"paper-phergain-lancet-oncol-2021","kind":"paper","name":"Chemotherapy de-escalation using an 18 F-FDG-PET-based pathological response-adapted strategy in patients with HER2-positive early breast cancer (PHERGain): a multicentre, randomised, open-label, non-comparative, phase 2 trial","route":"/key-papers/paper-phergain-lancet-oncol-2021/"}],"pairing":[{"id":"pet-adapted-her2-deescalation","kind":"pairing","name":"Early FDG-PET response → chemotherapy omission (HER2+)","route":"/pairings/pet-adapted-her2-deescalation/"}],"idea":[{"id":"idea-tdxd-first-then-nothing","kind":"idea","name":"Can T-DXd alone cure early HER2-positive disease?","route":"/ideas/idea-tdxd-first-then-nothing/"}],"roadmap":[{"id":"trial-modernisation-roadmap","kind":"roadmap","name":"Trial modernisation roadmap: the randomised trial → platforms and adaptive designs → decentralised, pragmatic and always-on","route":"/roadmaps/trial-modernisation-roadmap/"}]}}