Molnupiravir and Paxlovid are particularly exciting because antivirals that effectively target viruses at specific points in their life cycle are the “holy grail” of viral therapeutics—as past experience with other viruses has shown. Infection with HIV was fatal for nearly all patients until antivirals were developed against enzymes crucial to viral replication and researchers figured out how to combine those drugs to maximize their effectiveness and limit the emergence of resistant viral strains. These changes revolutionized HIV treatment, massively improving the prognosis for people who had access to antivirals. Instead of developing severe illness, treated patients could live healthily and expect normal life spans.
The development of these highly active oral antivirals for HIV infection took a decade and a half after the disease first came to light; the incredible progress in COVID-19 therapeutics took 18 months. Intriguingly, the COVID-19-treatment research borrowed many ideas from the HIV field; the two new COVID-19 drugs focus on similar pathways in the viral life cycle that HIV drugs target. In essence, these drugs prevent the target virus from reproducing itself. Because they work differently from the majority of COVID-19 vaccines, which teach the immune system to identify and attack the coronavirus’s characteristic spike protein, the antivirals remain effective against mutant variants whose spike proteins are harder for immune cells to recognize. Designing, manufacturing, and distributing vaccines updated for new variants will take time, so the availability of antivirals will be all the more essential.