Regorafenib as Salvage Treatment in Korean Patients with Refractory Metastatic Colorectal Cancer

PURPOSE: Regorafenib, an oral multi-targeted tyrosine kinase inhibitor, is considered the new standard of care in patients with chemotherapy-refractory colorectal cancers (CRCs). However, there are no data on this drug in Korean patients. MATERIALS AND METHODS: We evaluated patients who received oral regorafenib 160 mg once daily during the first 3 weeks of each 4-week cycle between August 2013 and September 2013. All patients had previously progressed fluorouracil, irinotecan, and oxaliplatin with or without biologic agents such as cetuximab or bevacizumab. RESULTS: Thirty-two patients were enrolled (median age, 57 years; male:female ratio, 20:12; Eastern Cooperative Oncology Group performance status [0-1:2], 31:1; colon:rectum, 21:11). The overall response rate was 3.1% and the disease control rate was 50.0% (95% confidence interval [CI]) with one partial response and 15 patients with stable disease. The median progression-free survival was 4.2 months (95% CI, 3.1 to 5.2 months) and the median overall survival has not yet been reached. The most common adverse events of grade two or higher related to regorafenib were hand-foot skin reaction (25%), mucositis (19%), abdominal pain (9%), and liver function test (LFT) abnormalities (9%). Grade 3 or 4 toxicities included LFT abnormalities (9%), abdominal pain (9%), rash (6%), anemia (3%), leukopenia (3%), neutropenic fever (3%), and fatigue (3%). There was no treatment-related death. CONCLUSION: Regorafenib appears to have promising activity and tolerable toxicity profiles in Korean patients with refractory CRC, consistent with the CORRECT trial findings.