Daiichi Sankyo has dosed the first patient in its Phase II trial examining the safety and efficacy of DS-8201 to treat patients with HER2-expressing advanced colorectal cancer who have received at least two prior lines of standard treatment.
The first part of the study will enrol patients with HER2-positive (defined as IHC3+ or IHC2+/ISH+) advanced colorectal cancer. This part of the trial is expected to enrol around 50 patients in North America, Europe and Japan.
Its primary endpoint is overall response rate, while secondary endpoints include progression-free survival, overall survival, duration of response, disease control rate, pharmacokinetics and safety.
Exploratory endpoints of the study feature time to response and biomarker analysis.
After the results of the first part of the study, Daiichi Sankyomight will begin two additional exploratory cohorts that will enrol patients whose tumours have lower levels of HER2-expression.
Daiichi Sankyo Oncology Research and Development executive vice-president and global head Antoine Yver said: “Given the existing unmet medical need for advanced colorectal cancer, we are exploring the smart delivery of chemotherapy with DS-8201 as a potential new type of targeted treatment for patients with HER2-expressing disease who have progressed on or become resistant to standard therapies.
“Similar to our breast and gastric cancer programmes, we are pursuing a development path focused first on patients with HER2-overexpressing tumours followed by potential expansion to include patients with advanced colorectal cancer with lower levels of HER2 expression.”
Currently, around 3% of colorectal cancers are estimated to overexpress the HER2 protein, which is a well-established therapeutic target in breast and gastric cancer.
No approved HER2-targeting therapies are currently available for patients with colorectal cancer.