{"entity":{"id":"nci9673","kind":"trial","name":"NCI9673","aka":["NCI 9673","ETCTN 9673"],"tldr":"NCI9673 was the first completed immunotherapy trial in anal cancer: nivolumab on its own shrank tumours in a quarter of heavily treated patients, which made PD-1 blockade a standard later option, but the follow-on randomisation showed that adding ipilimumab did not help and added toxicity.","summary":"NCI9673 was a multi-institutional phase 2 trial of the NCI Experimental Therapeutics Clinical Trials Network. Part A gave nivolumab to 37 patients with previously treated metastatic anal squamous cell carcinoma; part B randomised further patients to nivolumab alone or nivolumab with ipilimumab, with progression-free survival as the primary endpoint.\n\nIn part A nine of 37 patients responded (24 percent), including two complete responses, with few grade 3 events and no serious adverse events, which established PD-1 blockade as an option after chemotherapy. In part B median progression-free survival was 2.9 months with nivolumab and 3.7 months with the combination (hazard ratio 0.86, p 0.25), response rates were similar (17.4 against 21.5 percent), and grade 3 or worse treatment-related adverse events doubled with ipilimumab (25 against 12 percent). The corpus's metastatic anal cancer page cites NCI9673 for nivolumab after chemotherapy.","status":"mixed","asOf":"2026-09-22","links":[{"label":"ClinicalTrials.gov NCT02314169","url":"https://clinicaltrials.gov/study/NCT02314169"}],"tags":["soc-trials"],"related":[],"cancers":["metastatic-anal-cancer","anal"],"sections":[],"technologies":["checkpoint-inhibitor"],"targets":[],"drugs":["nivolumab","ipilimumab"],"companies":[],"institutions":["md-anderson"],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-nci9673-nivolumab-metastatic-anal-cancer-morris-lancet-oncol-2017","paper-nci9673-part-b-nivolumab-ipilimumab-anal-cancer-morris-jco-2026"],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT02314169","phase":"2","setting":"Refractory metastatic squamous cell carcinoma of the anal canal after prior chemotherapy: single-arm nivolumab (part A), then a randomised comparison of nivolumab with or without ipilimumab (part B)","sponsor":"National Cancer Institute (NCI)","result":"Nivolumab alone: objective response 24 percent in 37 previously treated patients. Nivolumab with ipilimumab did not improve progression-free survival (3.7 against 2.9 months, hazard ratio 0.86) or response and doubled grade 3 or worse toxicity.","yearReported":2017,"enrolled":143,"enrolledBasis":"registry","outcomes":[{"endpoint":"Objective response rate, part A","primary":true,"unit":"%","arms":[{"name":"Nivolumab","n":37,"value":24,"note":"95% CI 15 to 33; 2 complete and 7 partial responses"}],"source":"https://doi.org/10.1016/S1470-2045(17)30104-3"},{"endpoint":"Progression-free survival, part B","primary":true,"unit":"months","arms":[{"name":"Nivolumab + ipilimumab","value":3.7,"note":"90% CI 2.0 to 5.6"},{"name":"Nivolumab","value":2.9,"note":"90% CI 1.9 to 3.8"}],"hr":0.86,"ci":[0.6,1.23],"p":"0.25","source":"https://doi.org/10.1200/JCO-25-00929"},{"endpoint":"Objective response rate, part B","unit":"%","arms":[{"name":"Nivolumab + ipilimumab","value":21.5},{"name":"Nivolumab","value":17.4}],"p":"0.89","source":"https://doi.org/10.1200/JCO-25-00929"},{"endpoint":"Overall survival, part B","unit":"months","arms":[{"name":"Nivolumab + ipilimumab","value":20},{"name":"Nivolumab","value":15.9}],"hr":0.98,"source":"https://doi.org/10.1200/JCO-25-00929"},{"endpoint":"Grade 3 or worse treatment-related adverse events, part B","unit":"%","arms":[{"name":"Nivolumab + ipilimumab","value":25,"note":"12 patients"},{"name":"Nivolumab","value":12,"note":"6 patients"}],"source":"https://doi.org/10.1200/JCO-25-00929"}]},"route":"/trials/nci9673/","neighbours":{"cancer":[{"id":"anal","kind":"cancer","name":"Anal cancer (squamous cell carcinoma)","route":"/cancers/anal/"},{"id":"metastatic-anal-cancer","kind":"cancer","name":"Metastatic and recurrent anal squamous cell carcinoma","route":"/cancers/metastatic-anal-cancer/"}],"technology":[{"id":"checkpoint-inhibitor","kind":"technology","name":"Immune checkpoint inhibitors","route":"/technologies/checkpoint-inhibitor/"}],"drug":[{"id":"ipilimumab","kind":"drug","name":"Ipilimumab","route":"/drugs/ipilimumab/"},{"id":"nivolumab","kind":"drug","name":"Nivolumab","route":"/drugs/nivolumab/"}],"institution":[{"id":"md-anderson","kind":"institution","name":"MD Anderson Cancer Center","route":"/institutions/md-anderson/"}],"paper":[{"id":"paper-nci9673-part-b-nivolumab-ipilimumab-anal-cancer-morris-jco-2026","kind":"paper","name":"NCI9673 part B: randomised phase 2 study of nivolumab with or without ipilimumab in refractory metastatic anal cancer","route":"/key-papers/paper-nci9673-part-b-nivolumab-ipilimumab-anal-cancer-morris-jco-2026/"},{"id":"paper-nci9673-nivolumab-metastatic-anal-cancer-morris-lancet-oncol-2017","kind":"paper","name":"NCI9673: nivolumab for previously treated unresectable metastatic anal cancer","route":"/key-papers/paper-nci9673-nivolumab-metastatic-anal-cancer-morris-lancet-oncol-2017/"}]}}