Background: Hemolytic anemia is one of the major adverse events of the combination therapy of interferon and ribavirin. Because of ribavirin-related hemolytic anemia, dose reduction is a common event in this therapy. In this clinical retrospective cohort study we have examined the suitable timing of ribavirin reduction in patients with hemolysis during combination therapy.
Methods: Thirty-seven of 160 patients who had HCV-genotype 1b, had high virus load, and received 24-week combination therapy developed anemia with hemoglobin level <10 g/dl or anemia-related signs during therapy. After that, these 37 patients were reduced one tablet of ribavirin (200 mg) per day. After reduction of ribavirin, 27 of 37 patients could continue combination therapy for a total of 24 weeks (group A). However, 10 of 37 patients with reduction of ribavirin could not continue combination therapy because their <8.5 g/dl hemoglobin values decreased to or anemia-related severe side effects occurred (group B). We assessed the final efficacy and safety after reduction of ribavirin in groups A and B.
Results: A sustained virological response (SVR) was 29.6% (8/27) in group A and 10% (1/10) in group B, respectively. A 34.4% (12/27) of SVR + biological response in group A was higher than 10% (1/10) in group B ( P = 0.051), with slight significance. With respect to hemoglobin level at the time of ribavirin reduction, a rate of continuation of therapy in patients with > or =10 g/dl hemoglobin was higher than that in patients with <10 g/dl ( P = 0.036).
Conclusions: Reduction of ribavirin at hemoglobin level > or =10 g/dl is suitable in terms of efficacy and side effects.