Vitamin D supplementation improves sustained virologic response in chronic hepatitis C (genotype 1)-naïve patients

Abstract

Aim: To determine whether adding vitamin D, a potent immunomodulator, improves the hepatitis C virus (HCV) response to antiviral therapy.

Methods: Seventy-two consecutive patients with chronic HCV genotype 1 were randomized into two groups: the treatment group (n = 36, 50% male, mean age 47 ± 11 years) received Peg-α-2b interferon (1.5 μg/kg per week) plus ribavirin (1000-1200 mg/d) together with vitamin D3 (2000 IU/d, target serum level > 32 ng/mL), and the control group (n = 36, 60% male, mean age 49 ± 7 years) received identical therapy without vitamin D. HCV-RNA was assessed by real-time polymerase chain reaction (sensitivity, 10 IU/mL). The sustained virologic response (SVR) was defined as undetectable HCV-RNA at 24 wk post-treatment.

Results: Clinical characteristics were similar in both groups. The treatment group had a higher mean body mass index (27 ± 4 kg/m² vs 24 ± 3 kg/m²; P < 0.01), viral load (50% vs 42%, P < 0.01), and fibrosis score (> F2: 42% vs 19%, P < 0.001) than the controls. At week 4, 16 (44%) treated patients and 6 (17%) controls were HCV-RNA negative (P < 0.001). At week 12, 34 (94%) treated patients and 17 (48%) controls were HCV-RNA negative (P < 0.001). At 24 wk post-treatment (SVR), 31 (86%) treated patients and 15 (42%) controls were HCV-RNA negative (P < 0.001). Viral load, advanced fibrosis and vitamin D supplementation were strongly and independently associated with SVR (multivariate analysis). Adverse events were mild and typical of Peg-α-2b/ribavirin.

Conclusion: Adding vitamin D to conventional Peg-α-2b/ribavirin therapy for treatment-naïve patients with chronic HCV genotype 1 infection significantly improves the viral response.

Keywords: Fibrosis; Genotype 1; Hepatitis C; Sustained viral response; Vitamin D.

Figure 1

Vitamin D serum levels before and at 4 wk after the beginning of antiviral treatment + vitamin D supplementation (n = 36). Bars represent standard error.

Figure 2

Rate (%) of the rapid viral response and rate of early viral response in the treatment (n = 36) and control (n = 36) groups. RVR was defined as undetectable HCV RNA at 4 wk during treatment. Complete EVR (cEVR) was defined as undetectable HCV RNA at 12 wk during treatment. SOC: Standard of care; RVR: Rapid viral response; EVR: Early viral response; HCV: Hepatitis C virus; SVR: Sustained viral response.

Figure 3

Rate of sustained viral response in the treatment group (Vitamin D + SOC, n = 31/36) and the control group (n = 15/36, SOC) 6 mo after cessation of treatment. SVR was defined as undetectable HCV-RNA at 24 wk post-treatment. Bars represent standard error. SOC: Standard of care; SVR: Sustained viral response; HCV: Hepatitis C virus.