Zinc supplementation enhances the response to interferon therapy in patients with chronic hepatitis C

We evaluated the synergistic effect of zinc supplementation on the response to interferon (IFN) therapy in patients with intractable chronic hepatitis C in a pilot study using natural IFN-alpha with or without zinc. No clinic al differences were observed between patients treated with IFN alone (n = 4 0) and IFN with polaprezinc (IFN + Zn, n = 35). All patients were positive for HCV genotype Ib and had more than 10(5) copies of the virus/mL serum. T en million units of natural IFN-alpha was administered daily for 4 weeks fo llowed by the same dose every other day for 20 weeks. In the IFN + Zn group , patients received an additional dose of 150 mg/day polaprezinc orally thr oughout the 24-week, IFN course, No additional side-effects of polaprezinc were noted but four out of 40 IFN alone treatment and three out of 35 IFN Zn group withdrew because of side-effects. Complete response (CR) was defi ned as negative HCV RNA in the serum on PCR and normal amino-transferase le vel 6 months after therapy. Incomplete response (IR) was normal liver enzym e and positive serum HCV RNA. Both of them were evaluated at the 6 months a fter the completion of the treatment. Patients with higher levels of serum HCV (more than 5 x 10(5) copies/mL) had little response in both treatment g roups. Patients with moderate amount of HCV (10(5) to 4.99 x 10(5)/mL) show ed high response rates in combination group (CR: 11/27, 40.7%; CR + IR 15/2 7, 64.3%), better than IFN alone (CR: 2/15, 18.2%; CR + IR: 2/15, 18.2%). S erum zinc levels were higher in patients with IFN + Zn group than in the IF N group. Our results indicate that zinc supplementation enhances the respon se to interferon therapy in patients with intractable chronic hepatitis C.