A far more pronounced effect of low dose ribavirin was observed in patients with one of the following baseline characteristics: age ≥ 24, elevated ALT level, history of splenectomy, HCV genotype 1, viral load < 600,000 IU/mL, serum ferritin < 2006 ng/mL, liver modified-HAI fibrosis of 0 to 4 and previous treatment failure. This evidence concerns the gene GPT and fibrosis.