Seattle Genetics presents data from single arm Phase 2 MOUNTAINEER trial
Seattle Genetics announced that initial data were presented from the single arm phase 2 clinical trial known as MOUNTAINEER. The trial is evaluating the investigational agent tucatinib in combination with trastuzumab in patients with HER2-positive, RAS wild-type metastatic colorectal cancer after treatment with first- and second-line standard-of-care therapies. The regimen demonstrated antitumor activity and was well tolerated. Objective response rate was 52.2% with a median duration of response of 10.4 months. Median progression-free survival was 8.1 months. Median overall survival was 18.7 months. The combination of tucatinib and trastuzumab was well tolerated. The most common treatment-related adverse events were Grade 1 in severity. There were no Grade 4 or 5 treatment-related adverse events.