liver dwere gastrointestinal events, fatigue, and liver dysfunction. The rate of discontinuation of study drug due to adverse events, however, was similar in both groups. This was the first phase III study A66 of a systemic therapy to have shown a survival advantage in patients with advanced HCC. In this group of patients with advanced HCC, the median OS and time to radiologic progression were nearly 3 months longer for patients treated with sorafenib than those given placebo. This group of patientswas carefully selected,with the majority having eastern cooperative oncology group performance status of 0 or 1 and the remainder ECOG 2 status. They were CP Class A. 56 of the patients had HCV. A second similar study was conducted in Asia with 271 patients with advanced HCC. None had prior systemic therapy, and all had CP Class A.
This trial had no predefined primary endpoint, and the objective was to assess the efficacy and safety of sorafenib in Asia Pacific patients with advanced HCC. Median OS was 6.5 months in patients treated with sorafenib compared to 4.2 months in the placebo group, hazard ratio 0.68. Median time to progression was 2.8 months in the sorafenib group and 1.4 months in the placebo group. There was no significant difference in the time to symptomatic progression between the two groups. Like in the previous studies, sorafenib was generally well tolerated with manageable side effects. The most common drug related adverse events in the sorafenib group were HFS, diarrhea, alopecia, fatigue, rash or desquamation, hypertension, and anorexia. These were predominantly grade 1 or 2 adverse events.
In comparison, overall incidence of HFS was 21 and diarrhea 39 in the SHARP study. In this Asian study, treatment discontinuation due to adverse events was similar in both groups. Dose reductions due to adverse events were required in 30.9 of patients in the sorafenib group compared to 2.7 in the placebo group. Most common reasons for dose reductions in the sorafenib group were HFS and diarrhea. Although the absolute survival was greater in the SHARP trial for both study groups, the hazard ratios for survival was comparable between the two studies. This suggests that there is comparable efficacy for sorafenib in both studies and that there are differences in the patient population in the two studies.
Indeed, at baseline, more patients had extrahepatic spread, greater number of hepatic tumor lesions, poorer ECOG status and higher alpha fetoprotein levels in the study by Cheng et al. than in the SHARP trial. It may well be than the patients enrolled in the former study had more advanced disease than those in the latter, accounting for the difference in the absolute survival for both sorafenib and placebo groups across the two studies. However, other significant differences exist between the two studies. As previously stated, etiological factors for HCC in the Asia Pacific region differ from other regions. For example, 73 of the patients in the study by Cheng