Will virology ever have a 'penicillin moment'?

In contrast to penicillin, which can kill different types of bacteria, the few antiviral drugs that are currently available on the market combat only specific viruses. This is due to the strategy of antiviral development involving the identification of a virus-specific target, screening for inhibitors, and optimizing lead compounds for maximal efficacy and minimal toxicity. The threat of emerging and re-emerging viruses emphasizes the need to develop broad-spectrum antivirals. The development of such drugs is very attractive because it implies a simplified clinical development and more practical aspects of treatment. As the two "broad-spectrum" antivirals currently in use, ribavirin and interferon-α, are both not very potent and treatment is associated with important side-effects, there is an urgent need for safer and more potent broad-spectrum antivirals. Different strategies are being employed to identify broad-spectrum antivirals of which we will discuss a few. For example, favipiravir, an inhibitor of influenza virus replication that is in clinical development, is able to block the replication of various other RNA viruses. Also nucleoside analogues such as 2’-C-methylcytidine have broad-spectrum antiviral properties. Drugs that are already FDA approved for other indications, and target host proteins required by multiple viruses, could be repurposed as for broad-spectrum antiviral therapy. The success of these and other currently explored approaches will affect the possibility of developing a broad-spectrum antiviral in the future.status: publishe