Repurposed Antivirals Effective Against Multiple Viruses
Viruses are small infectious agents of genetic material (either DNA or RNA) contained in a protective protein covering called a capsid. Viruses cannot survive in a host on their own; rather they must use the host cell’s metabolic machinery to survive. Viruses are usually species or organ-specific.
Virus particles use proteins in their capsid to attach to host cells through receptor molecules on the host cell surface. Once inside host cells, viruses take over the host cells’ metabolic machinery to multiply. Viruses may lie dormant for long periods of time, establish a persistent long-term infection without damaging the host cell, or kill host cells when they release daughter viruses.
Antibiotics used to treat bacteria are not effective for treating viruses. A number of antiviral agents have been developed to specifically treat certain viruses, most notably HIV, herpes viruses, and hepatitis B and C viruses.
According to the WHO, there is an urgent need for better control of viral diseases. Re-positioning existing safe-in-human antiviral agents from one viral disease to another could play a pivotal role in this process.
Therefore, an international team of scientists led by Denis Kainov from the Norwegian University of Science and Technology (NTNU), have now reviewed all approved, investigational and experimental antiviral agents, which are safe in man, and identified 59 compounds that target at least three viral diseases. The researchers then tested 55 of these compounds on eight different viruses and found that seven showed new effects against HIV-1, Zika virus, and Rift Valley Fever.
The researchers say that their results show existing safe-in-human BSAs could be used on other viral infections. The goal is to create broad-spectrum antiviral drugs, much like the broad-spectrum antibacterial drugs that are currently available.
“Effective treatment with broad-spectrum antivirals may shortly become available, pending the results of further pre-clinical studies and clinical trials. The most effective and tolerable compounds will expand the available therapeutics for the treatment of viral diseases,” said Aleksandr Kanevsky, the first author of the study and a Ph.D. student at NTNU.
“We hope that not only broad-spectrum antibiotics but also broad-spectrum antivirals will be available in the future,” said Magnar Bjørås, a professor at NTNU’s Department of Molecular Medicine. “These drugs could be used as the first-line therapeutics to combat emerging and re-emerging viral threats that have a global impact, improving preparedness and the protection of the general population from viral epidemics and pandemics.”