Seattle genetics, inc. announces initial results from mountaineer trial show antitumor activity of tucatinib combination in her2-positive metastatic colorectal cancer

Seattle genetics, inc. 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 (herceptin®) in patients with her2-positive (her2+), ras wild-type metastatic colorectal cancer (mcrc) after treatment with first- and second-line standard-of-care therapies. the regimen demonstrated encouraging antitumor activity and was well tolerated. tucatinib is an oral, small molecule tyrosine kinase inhibitor that is highly selective for her2. her2 amplification or overexpression occurs in approximately three-to-five% of all patients with mcrc.1,2 the results were presented during a poster discussion session at the european society for medical oncology (esmo) 2019 congress in barcelona, spain (abstract #527pd). initial results from 23 patients evaluable for clinical/radiographic response are below; objective response rate (orr) was 52.2%(95% confidence interval [ci], 30.6-73.2) with a median duration of response of 10.4 months (95% ci, 6.0-ne); median progression-free survival (pfs) was 8.1 months (95% ci, 3.8-ne); and median overall survival (os) was 18.7 months (95% ci, 12.3-ne). the combination of tucatinib and trastuzumab was well tolerated. the most common treatment-related adverse events were grade 1 in severity and included increased aspartate aminotransferase (ast, 38.5%; all grade 1) increased alanine aminotransferase (alt, 23.1%; all grade 1), and diarrhea (23.1%; one grade 1, four grade 2, one grade 3). there were no grade 4 or 5 treatment-related adverse events.
SGEN Ratings Summary
SGEN Quant Ranking