{"entity":{"id":"atempt","kind":"trial","name":"ATEMPT","aka":[],"tldr":"ATEMPT tested whether a year of the antibody-drug conjugate T-DM1 could replace chemotherapy plus trastuzumab for the smallest HER2-positive breast cancers; almost no one relapsed on T-DM1, but it was not less toxic overall, so it is an alternative rather than a replacement.","summary":"The APT trial had shown that paclitaxel plus trastuzumab cures almost all node-negative HER2-positive tumours of 3 cm or less. ATEMPT randomised 497 patients with stage I HER2-positive breast cancer three to one to 17 cycles of trastuzumab emtansine or to the APT regimen. The co-primary endpoints were invasive disease-free survival with T-DM1 and a comparison of clinically relevant toxicities.\n\nThree-year invasive disease-free survival with T-DM1 was very high, but the rate of clinically relevant toxicity was similar in the two arms, so the toxicity endpoint was not met; T-DM1 caused more thrombocytopenia and liver enzyme rises, paclitaxel more neuropathy and alopecia. T-DM1 is now listed as an alternative adjuvant option for stage I disease, especially for patients who wish to avoid chemotherapy side effects.","status":"mixed","asOf":"2026-09-17","links":[{"label":"ClinicalTrials.gov NCT01853748","url":"https://clinicaltrials.gov/study/NCT01853748"}],"tags":["subtype-trials"],"related":[],"cancers":["her2-positive-early-breast-cancer","breast-her2-positive","breast-cancer"],"sections":[],"technologies":[],"targets":[],"drugs":["trastuzumab-emtansine","paclitaxel","trastuzumab"],"companies":["roche-genentech"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":["sara-tolaney"],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT01853748","phase":"2","setting":"Stage I HER2-positive breast cancer: one year of trastuzumab emtansine against paclitaxel plus trastuzumab (the APT regimen)","sponsor":"Dana-Farber Cancer Institute","result":"Very high three-year invasive disease-free survival with one year of trastuzumab emtansine in stage I disease, but clinically relevant toxicity was not lower than with paclitaxel plus trastuzumab.","yearReported":2021,"enrolled":512,"outcomes":[]},"route":"/trials/atempt/","neighbours":{"cancer":[{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-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/"}],"drug":[{"id":"paclitaxel","kind":"drug","name":"Paclitaxel / nab-paclitaxel","route":"/drugs/paclitaxel/"},{"id":"trastuzumab","kind":"drug","name":"Trastuzumab","route":"/drugs/trastuzumab/"},{"id":"trastuzumab-emtansine","kind":"drug","name":"Trastuzumab emtansine","route":"/drugs/trastuzumab-emtansine/"}],"company":[{"id":"roche-genentech","kind":"company","name":"Roche / Genentech","route":"/companies/roche-genentech/"}],"person":[{"id":"sara-tolaney","kind":"person","name":"Sara M. Tolaney","route":"/people/sara-tolaney/"}]}}