Why an Interferon ?
Interferons have three main properties:
Anti-Viral - suppress viral replication
Immuno-stimulatory - drive anti-viral immune responses
Anti-proliferative - suppress the turnover of infected cells
This combination of activities are ideal for eliminating persistent viral infections such as Hepatitis B and Hepatitis C. Drugs targeted at the virus alone can only suppress the virus and are unable to cure the infection as has been seen with HIV and Hepatitis B. We have already seen that up to 50% of patients with Hepatitis C can be cured; our aim is to substantially increase this figure.
Interferon alpha 8 (IFN-α8)
This constitutes Riotech’s lead program. IFN-a8 is the most potent type 1 interferon in anti-viral assays and one of the top 3 interferons for stimulating Th1 type immune responses.
RioTech has expressed a purified recombinant interferon α8 and compared this product to a panel of type I interferons and to a commercial preparation of Interferon α2. There are 14 different human type 1 IFNs all of which possess anti-viral, immunomodulatory and anti-proliferative functions. The IFNs differ both qualitatively and quantitatively in the degree to which these responses are stimulated. Clearance of chronic HCV requires an IFN with strong anti-viral properties in liver cells and which stimulates a powerful TH1 type response.
Based upon current development plans it is estimated that Phase I clinical trials would start in 18 months time.
Host Small Molecule Target
Riotech’s first therapeutic program in the small molecule area is for inhibitors of a host enzyme which results in enhanced natural immune response against HCV. Furthermore specific inhibitors of this enzymatic target would only amplify interferon induced processes in virally infected cells. RioTech has developed an assay which screens small molecules for specific inhibitors.