Antiviral drug

Lore & Background

The first experimental antivirals were developed in the 1960s, mostly to deal with herpes viruses, using traditional trial-and-error drug discovery methods. Researchers grew cell cultures, infected them with the target virus, and introduced chemicals that might inhibit viral activity, observing whether virus levels rose or fell. This process was time-consuming and inefficient without detailed knowledge of viral function. Only in the 1980s, when full genetic sequences of viruses began to be unraveled, did researchers learn how viruses worked in detail and what chemicals were needed to thwart their reproductive cycle.

Reader's Guide

Antiviral drugs emerged from a greatly expanded knowledge of genetic and molecular function, allowing researchers to understand virus structure and function. The pressure to deal with HIV, the cause of AIDS, accelerated development. Modern antiviral design identifies viral proteins or parts that can be disabled, targeting components unlike human proteins to reduce side effects. Targets should be common across strains or virus families for broad effectiveness.

Researchers attack viruses at every stage of their life cycle, from attachment and entry to replication and release. Entry inhibitors like enfuvirtide block viral fusion with host cells, while uncoating inhibitors such as amantadine and pleconaril interfere with viral uncoating. Despite advances, viral variation remains a major difficulty in developing vaccines and antivirals.

Did You Know?

• Some species of mushrooms have been found to contain multiple antiviral chemicals with synergistic effects.
• Pleconaril works against rhinoviruses by blocking a pocket on the virus surface that controls uncoating.