The coronavirus disease 2019 (Covid-19) pandemic continues to spread rapidly worldwide, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into variants with increasing transmissibility and capability of evading human immunity (e.g., the B.1.1.529 [omicron] variant). A widespread and timely distribution of efficacious antiviral therapy is an important part of the response.
Currently, nirmatrelvir–ritonavir is recommended by World Health Organization (WHO) guideline for treating mild-to-moderate Covid-19. Nirmatrelvir is an oral inhibitor of the SARS-CoV-2 3-chymotrypsin–like cysteine protease enzyme that can be dispensed at community pharmacies and has been authorized for emergency use by many countries. However, access to nirmatrelvir is limited worldwide.