The search for antivirals for covid-19

Antivirals are one of the most sought after, yet missing, tools to control SARS-COV-2. Chris Stokel-Walker asks what was learnt from a similar search nearly 20 years ago Antiviral drugs are among the most researched tools for treating covid-19. They either prevent a virus entering a host cell or prevent it from being able to replicate once it is inside. And yet, over 18 months into the pandemic, finding ones that are effective against SARS-CoV-2 has proved challenging. Remdesivir was an early frontrunner—and many governments were desperate enough to grant it emergency use approval despite limited evidence. Those early hopes were ultimately dashed when major studies, notably the World Health Organization’s Solidarity trial, found it to be ineffective at preventing death (although it did help patients already recovering do so marginally faster). Doctors in Japan have treated covid-19 patients with favipiravir, an influenza antiviral, but the drug has previously been linked to birth defects