Abstract
The previous retrospective study suggested that dosing vitamin K may enhance the anticancer action of sorafenib against hepatocellular carcinoma. To confirm it, we performed a phase II, randomized, open-label study. Patients with hepatocellular carcinoma were randomly assigned to receive sorafenib + vitamin K2 (menatetrenone, 45 mg daily, orally) or sorafenib only. Between 1 May 2012 and 1 May 2016, 68 patients were screened. Forty-four eligible patients were assigned at a 1:1 ratio to each cohort. The objective response rate in the vitamin K-dosed group was significantly higher than that in the sorafenib only group (27.3% vs 4.5%, respectively; p = 0.039). The median time of progression-free survival was significantly extended in the vitamin K-dosed group compared with the sorafenib only group (4.9 months vs 2.7 months, respectively; hazard ratio (HR), 0.44; 95% confidence interval (CI): 0.21-0.89; p = 0.018). Although there was no significant difference between the two groups in the median time of overall survival, patients in the vitamin K-dosed group with a complete response or partial response achieved a significantly extended median time of overall survival compared with the other patients in the vitamin K-dosed group or the patients in the sorafenib only group (26.1 months vs 9.0 months; HR, 0.34; 95% CI: 0.11-0.95; p = 0.046 or 11.5 months; HR, 0.16; 95% CI: 0.034-0.70; p = 0.006, respectively). Dosing vitamin K could augment the anticancer action of sorafenib against HCC.