vitamin d in standard hcv regimen (peg-interferon plus ribavirin), its effect on the early virologic response rate: a clinical trial

Background: patients chronically infected with the hepatitis c virus (hcv) are more likely to have vitamin d deficiency recent studies revealed that vitamin d has immunomodulator and antiviral properties and can enhance the effect of interferon on the hcv virus. objectives: we aimed to assess the influence of vitamin d supplementation on viral response to peginf/rbv therapy. patients and methods: in a randomized-controlled trial 66 patients with hcv (30 with genotype 1or 4 and 36 with genotype 2 or 3) were randomly divided into two groups in gastroenterology clinic: the study group (n = 34) received oral vitamin d supplementation (1600 iu/day) to maintain serum levels > 30 ng/ml besides the routine treatment of 180 g peginf 2a plus oral ribavirin. the control group (n = 32) received the same treatment without vitamin d supplementation. the primary outcome was undetectable hcvrna at week 12 of treatment, referred to as complete early viral response (cevr). realtime polymerase chain reaction (sensitivity: 10 iu/ml) was used to assess hcv rna. serum vitamin d levels were measured at baseline and weeks 4, 8, 12 and 24 of treatment. spearman’s correlation showed that baseline vitamin d correlated with the stage of liver fibrosis in both study and control group (p = 0.04, r = 0.57). results: there were no significant differences in baseline characteristics between two groups except serum ast level. complete evr rate at week 12 in the vitamin d group was significantly higher than the controls (100% vs 84.4%; p = 0.023) whereas this figure was not significant when genotypes 1 and 4 or 2 and 3 in the test group were compared to those of the control (100% vs 86.7%; p = 0.19 and 100% vs 82.4%; p = 0.22). serum vitamin d levels were lowest at baseline (2215 ng/ml), but increased after 12 weeks of vitamin d therapy to a mean level of 5238 ng/ml (p = 0.02) in study group. conclusions: the addition of vitamin d to conventional pegifn/rbv therapy in hcv patients may significantly improve the viral response.