Antiviral drug resistance

Use the right antiviral drug and hit the virus hard

In the past few years we have witnessed the emergence of a new strand of antimicrobial treatment—antiviral drugs. Those currently available include amantadine (against influenza A virus), tribavirin (respiratory syncytial virus), ganciclovir (cytomegalovirus), aciclovir, valaciclovir, famciclovir, foscarnet (all active against the herpes viruses), and the antiretroviral drugs zidovudine, didanosine, and zalcitabine. Important advances have been made in reducing the incidence of life threatening opportunistic infections in recipients of transplants, successfully treating respiratory infections such as respiratory syncytial virus bronchiolitis and severe influenza A, and more recently in dramatically reducing HIV viral load by combination antiretroviral therapy. Further targets of antiviral agents in the near future will include hepatitis B, hepatitis C (interferons currently provide limited benefit for carriers of either virus), the common cold virus, and papillomaviruses. The impetus for and scientific rationale of antiviral drug development have been greatly enhanced by the HIV epidemic; at least five new antiretroviral drugs are near to licensing, in addition to the three currently available in Britain. The tremendous investment by the pharmaceutical industry in discovering antiviral drugs ensures a continued expansion in the antiviral armoury.

However, amid this euphoria the potential for antiviral drug resistance must not be forgotten. …