Mean peginterferon alfa-2a trough concentration at week 12 was 11.74.3 ng/mL for 180 g and 23.411.3 ng/mL for 360 g. Early VK profiles suggested a trend towards an enhanced viral decline in the 360 g groups with a mean decrease in HCV RNA at 48 hours post first dose of 1.04 log10 ( IU/mL ) compared with 0.76 log10 ( IU/mL ) in the 180 g groups .