CLINICAL RELEVANCE OF ANTIINTERFERON ANTIBODIES IN THE SERUM OF CHRONIC HEPATITIS-C PATIENTS TREATED WITH INTERFERON-ALPHA

The development of anti-interferon (anti-HFN) antibodies in the serum of patients undergoing antiviral therapy has been postulated as one po ssible cause of interpatient variability in response to therapy. We an alyzed the relationship between the appearance of anti-IFN antibodies and the loss of response to interferon-alpha (IFN-alpha), as character ized by a breakthrough of serum aminotransferase after a period of com plete biochemical remission. The analysis involved clinical trials whe re neutralizing anti-IFN antibodies were detected by standardized and comparable methods, The results show that a time relationship between breakthrough and anti-IFN antibodies is observed in only a few cases a nd is independent of the type of IFN-alpha preparation used. Thus, cau ses of IFN resistance other than anti-IFN antibodies must also be impl icated in most breakthrough cases. Another potential is the selection of drug-resistant viral strains, Current rational behavior following t he appearance of breakthrough (from whatever cause) in clinical practi ce advocates changing treatment to a different type of IFN-alpha. The detection of anti-IFN enzyme-linked immunosorbent assay (ELISA) antibo dies or IFN neutralizing antibodies does not appear to provide any add itional information for decision making.