{"entity":{"id":"paper-oh-destiny-pantumor02-biliary-pancreatic-esmo-open-2026","kind":"paper","name":"Efficacy and safety of trastuzumab deruxtecan in patients with HER2-expressing biliary tract or pancreatic tumors: a subgroup analysis of DESTINY-PanTumor02","aka":[],"tldr":"In the tumour-agnostic trial that led to the HER2 IHC 3+ approval, trastuzumab deruxtecan shrank about a quarter of 41 pretreated biliary cancers overall and more than half of those with the strongest HER2 stain, while pancreatic tumours barely responded.","summary":"DESTINY-PanTumor02 (NCT04482309) Part 1 evaluated trastuzumab deruxtecan 5.4 mg/kg in locally advanced or metastatic HER2 IHC 3+ or 2+ tumours (local or central testing) that had progressed after systemic treatment or had no treatment options. The primary endpoint was investigator-assessed objective response rate; this report covers the biliary tract (41 patients) and pancreatic (25 patients) cohorts, with median follow-up of 6.0 and 5.0 months.\n\nBy investigator, objective response rate was 22.0% (95% CI 10.6 to 37.6) in biliary tract cancer and 4.0% (0.1 to 20.4) in pancreatic cancer; by independent central review 26.8% and 12.0%. Responses were seen across most biliary subgroups, with the highest rate, 56.3% (95% CI 29.9 to 80.2), in centrally confirmed HER2 IHC 3+ tumours. Stable disease was the best response in 61.0% of the biliary cohort; median overall survival was 7.0 months (95% CI 4.6 to 10.2). Adjudicated drug-related interstitial lung disease or pneumonitis occurred in 17.1% of biliary patients and 4.0% of pancreatic patients.","asOf":"2026-09-24","links":[{"label":"Oh et al., ESMO Open 2026: trastuzumab deruxtecan in the biliary and pancreatic cohorts of DESTINY-PanTumor02","url":"https://doi.org/10.1016/j.esmoop.2026.108344"},{"label":"PubMed","url":"https://pubmed.ncbi.nlm.nih.gov/42531802/"},{"label":"ClinicalTrials.gov NCT04482309","url":"https://clinicaltrials.gov/study/NCT04482309"}],"tags":[],"related":[],"cancers":["gallbladder","biliary-tract-cancer","cholangiocarcinoma","pancreatic"],"sections":[],"technologies":[],"targets":["her2"],"drugs":["trastuzumab-deruxtecan"],"companies":["astrazeneca","daiichi-sankyo"],"institutions":[],"pathways":[],"terms":[],"trials":["destiny-pantumor02"],"people":["oh-do-youn"],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"journal":"ESMO Open","year":2026,"doi":"10.1016/j.esmoop.2026.108344","pmid":"42531802","authors":"Oh DY, Lugowska I, Stroyakovskiy D, et al.","paperType":"observational","findings":["Biliary cohort (n = 41): objective response rate 22.0% by investigator, 26.8% by central review; 56.3% in centrally confirmed IHC 3+ tumours.","Pancreatic cohort (n = 25): 4.0% by investigator.","Interstitial lung disease or pneumonitis in 17.1% of biliary patients; median overall survival 7.0 months."],"whatItMeans":"The IHC 3+ subgroup result is why the tumour-agnostic label is written at 3+ and not 2+, and why a gallbladder cancer with a strong HER2 stain now has two on-label choices (zanidatamab, trastuzumab deruxtecan) after chemotherapy. Lung toxicity again ran higher than in breast cancer.","caveats":["Subgroup of a single-arm basket study; local and central HER2 testing were both allowed.","Short follow-up and small IHC 3+ subgroup (16 patients)."],"changedPractice":false,"participants":66},"route":"/key-papers/paper-oh-destiny-pantumor02-biliary-pancreatic-esmo-open-2026/","neighbours":{"cancer":[{"id":"biliary-tract-cancer","kind":"cancer","name":"Biliary tract cancer (all types)","route":"/cancers/biliary-tract-cancer/"},{"id":"cholangiocarcinoma","kind":"cancer","name":"Biliary tract cancer (cholangiocarcinoma)","route":"/cancers/cholangiocarcinoma/"},{"id":"gallbladder","kind":"cancer","name":"Gallbladder cancer","route":"/cancers/gallbladder/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"}],"target":[{"id":"her2","kind":"target","name":"HER2","route":"/targets/her2/"}],"drug":[{"id":"trastuzumab-deruxtecan","kind":"drug","name":"Trastuzumab deruxtecan","route":"/drugs/trastuzumab-deruxtecan/"}],"company":[{"id":"astrazeneca","kind":"company","name":"AstraZeneca","route":"/companies/astrazeneca/"},{"id":"daiichi-sankyo","kind":"company","name":"Daiichi Sankyo","route":"/companies/daiichi-sankyo/"}],"trial":[{"id":"destiny-pantumor02","kind":"trial","name":"DESTINY-PanTumor02","route":"/trials/destiny-pantumor02/"}],"person":[{"id":"oh-do-youn","kind":"person","name":"Do-Youn Oh","route":"/people/oh-do-youn/"}],"biomarker":[{"id":"her2-ihc-3-plus","kind":"biomarker","name":"HER2 IHC 3+ (HER2-positive by immunohistochemistry)","route":"/biomarkers/her2-ihc-3-plus/"}]}}