Interferon lambda as a potential new therapeutic for hepatitis C.

Interferon lambdas (IFN-lambda) are Type III interferons with biological activity, including induction of antiviral genes, similar to Type I IFNs, but signal through a distinct receptor complex. The expression pattern for the IFN-lambda receptor is more cell specific than the widely distributed IFN-alpha receptor, suggesting in vivo, IFN-lambda may have fewer side effects than IFN-alpha, such as less hematologic toxicities. A PEGylated form of IFN-lambda (PEG-rIL-29) was well tolerated in animals and did not result in hematologic toxicity. Clinical data from initial studies of PEG-rIL-29 has demonstrated antiviral effects in patients with hepatitis C without producing hematologic toxicity. These preclinical and early clinical data support PEG-rIL-29 as a potential new therapeutic agent for treatment of patients with hepatitis C.