A LEADING British biochemist has developed an antiviral drug which he believes will reduce HIV and Hepatitis infection to undetectable levels leaving patients virtually symptom-free.
Prof Raymond Dwek, director of the Glycobiology Institute at Oxford University, is pioneering a new approach to antiviral medicine based on the manipulation of sugar chains or glycans which are attached to proteins on the surface of cells.
He will outline the therapeutic potential of his research at a conference today in Trinity College, Dublin hosted by the newly formed Glycoscience Ireland group.
Prof Dwek wants to initiate trials of his antiviral drug NB-DNJ (N-butyl-deoxynojirimycin) on Hepatitis C sufferers in Ireland because of the large cohort of patients infected by contaminated blood products in the 1980s and 1990s.
NB-DNJ was developed by Prof Dwek and his team at Oxford in the mid-1980s as an Aids drug but is now widely used in the treatment of glycolipid storage disorders like Tay-Sachs and Gaucher's disease.
At present the standard care for Hepatitis C involves a combination of the antiviral drugs Ribavirin and Interferon.
But this treatment causes debilitating flu-like symptoms in around 50 per cent of patients and many appear to develop a resistance to the drugs over time. Moreover, when patients are taken off the drugs, their virus load can often rebound to a higher level.
In laboratory tests on Hepatitis C cultures, Prof Dwek said he has found that the disease disappears when following up a typical course of Ribavirin-Interferon with NB-DNJ.
"The approach differs from normal antiviral therapy in that it targets the host cells rather than the virus, inhibiting the virus from attaching or docking in the cells," he said.
Prof Dwek believes the drug will similarly reduce the level of HIV infection to an undetectable level.
"We cannot cure a HIV patient because the virus is already integrated into the DNA but we can suppress the disease to a level where the virus tide would go to zero and the patient could carry on as normal," he said.
Globally, more than two billion people are infected with Hepatitis B, 200 million with Hepatitis C and 40 million with HIV. The prevalence of these viruses in part reflects their ability to mutate. About 20,000 people a year in the US contract a strain of HIV, which is resistant to all the combinations of retroviral therapy.
The unique advantage of using NB-DNJ as an antiviral, explained Prof Dwek, is that because it targets the host cell, it is "mutation-proof".
The initial problem for Prof Dwek and his team is finding a suitable delivery vehicle to administer the drug to patients and to establish what constitutes a safe amount.
There are plans for a series of toxicology tests in the US later this year specifically aimed at HIV sufferers.
