Incidence, risk factors and impact on virological response of anemia in chronic genotype 2 hepatitis C receiving sofosbuvir plus ribavirin

Background/Purpose: The major dose-limiting toxicity of ribavirin is hemolytic anemia. We investigated the incidence, risk factors and impact on virological response of anemia in chronic hepatitis C genotype 2 patients receiving sofosbuvir plus ribavirin therapy. Methods: This was a retrospective real-world analysis of a single center including 293 chronic hepatitis C genotype 2 patients treated with sofosbuvir plus ribavirin for 12 weeks. Severe anemia was defined as hemoglobin concentration <10 g/dl. Results: Treatment was completed in 285 (97%) of patients, of whom one withdrew due to severe anemia. Ribavirin dose reduction was required in 88 (30%) of patients. After excluding those with baseline hemoglobin <10 g/dl, 79 (29%) patients had developed severe anemia during therapy. Stepwise logistic regression analysis identified that chronic kidney disease (odds ratio [OR] = 3.970, p < 0.001), baseline hemoglobin level (OR = 0.475, p < 0.001) and baseline platelet count (OR = 0.992, p = 0.022) were independent factors. The sustained viral response 12 weeks off therapy (SVR₁₂) rate was 93.9% in the per-protocol population. Multivariate analyses showed that history of hepatocellular carcinoma significantly reduced the efficacy of sofosbuvir plus ribavirin therapy (OR = 0.172, p = 0.001). Severe anemia, dose reduction or average dose (mg/kg/day) of ribavirin was not associated with SVR₁₂. Conclusion: Severe anemia was not uncommon during sofosbuvir plus ribavirin therapy for chronic hepatitis C genotype 2 patients. Careful monitoring of anemia is necessary in patients with chronic kidney disease and low baseline hemoglobin level and platelet count.