New research has found that drug-resistant variants of SARS-CoV-2, the virus that causes COVID-19, have emerged independently in different parts of the world, showing resistance to protease inhibitors like paxlovid and ensitrelvir. The study discovered that certain mutations present in circulating SARS-CoV-2 variants determine resistance to ensitrelvir, a protease inhibitor approved in Japan, in addition to nirmatrelvir, the active component of paxlovid. The findings suggest that protease inhibitors should be designed to avoid simple mutations to lower the risk of resistance. The study also revealed regional clusters of these drug-resistant variants, providing evidence for person-to-person transmission. The emergence of these drug-resistant variants underscores the need for ongoing monitoring and surveillance of the virus to inform the development of effective treatments and vaccines.

Read more: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(23)00225-6/fulltext