ArQule, Inc. (Nasdaq: ARQL) and Daiichi Sankyo Co., Ltd. (TSE: 4568) today announced final results from a randomized, placebo-controlled, double-blind, phase 2 clinical trial with the selective MET inhibitor tivantinib as a single-agent, investigational, second-line treatment in hepatocellular carcinoma (HCC). The data are to be presented today at the 48th Annual Meeting of the American Society of Clinical Oncology (ASCO) (abstract number 4006).
The 107 patients in the trial had unresectable HCC and had disease progression after first-line therapy or were unable to tolerate the first-line therapy. Patients were randomized to receive tivantinib at 360 milligrams (mg) twice daily or 240 mg twice daily or placebo (2:1 tivantinib:placebo). The primary endpoint was time to progression (TTP) in the intent to treat (ITT) population. Other study endpoints were disease control rate (DCR), progression free survival (PFS), overall survival (OS), as well as safety for the ITT population and pre-defined MET-high or MET-low cohorts (as defined by immunohistochemistry).
A statistically significant 56 percent improvement as compared to placebo was seen in TTP in the ITT population (hazard ratio [HR] = 0.64; log rank p-value = 0.04). In the MET-high cohort, there were also statistically significant improvements in TTP, PFS and OS:
- Median OS in tivantinib arm was 7.2 months and 3.8 months in the placebo arm (HR = 0.38; log rank p-value = 0.01)
- Median TTP was 2.9 months in the tivantinib arm and 1.5 months in the placebo arm (HR = 0.43, log rank p-value = 0.03)
- Median PFS was 2.4 months in the tivantinib arm and 1.5 months in the placebo arm (HR = 0.45, log rank p-value = 0.02).
Adverse events were reported at similar rates in the treatment and placebo arms of the trial, except for a higher incidence of fatigue and hematologic events, including neutropenia and anemia, in tivantinib-treated patients. The incidence of hematologic events decreased following dose reduction of tivantinib from 360 mg twice daily to 240 mg twice daily. Due to the incidence of neutropenia in the 360 mg treatment group, the tivantinib dose was reduced to 240 mg twice daily for all patients.