Combination therapy with interferon-alpha plus N-acetyl cysteine for chronic hepatitis C: a placebo controlled...

A small pilot study in patients with chronic hepatitis C (HCV) infection suggested that antiviral treatment with interferon (IFN) plus N-acetyl cysteine (NAC) was more effective than treatment with interferon alone [Beloqui et al. (1993) Journal of Interferon Research 13:279-282]. An attempt was made to confirm this by performing a placebo-controlled double-blind study at 8 medical centres in Spain and Italy. One-hundred forty-seven patients with chronic HCV infection were investigated, 73 received 3MU IFN-alpha thrice weekly plus NAC 1800 mg daily and 74 received IFN alone. Treatment was continued for 6 months and patients were followed up for a further 6 months. Amongst patients receiving IFN plus NAC, sustained virological responses were observed in 5.5%, transient responses in 26% and non-response in 68.5%. The figures for patients receiving IFN only were 4.1%, 24.3% and 71.6% respectively. Sustained virological response was significantly associated with non-type 1 genotypes (P = 0.045) and with low pre-treatment viraemia levels (P = 0.034). Biochemical response (serum ALT concentrations) correlated with virological outcome in 97% (n = 139) of cases. Patients who experienced a sustained virological response also showed reduction in the Knodell histological activity index. It is concluded that patients with chronic HCV infection are very unlikely to benefit from the addition of N-acetyl cysteine to conventional therapy with interferon-alpha.