DefinePK

Abstract

PaxlovidTM is a combination of Nirmatrelvir and Ritonavir antiviral pills with good oral bioavailability. In clinical studies, treatment of the patients infected with SARS-CoV-2 with PaxlovidTM within three to five days of the appearance of symptoms significantly reduced the hospitalization rate as well as mortality. It is the first oral antiviral treatment for the COVID-19 which received USFDA approval for EUA on 22nd December, 2021. Nirmatrelvir inhibits the replication of SARS-CoV-2 while another antiviral drug, Ritonavir, is given in combination to enhance the bioavailability of Nirmatrelvir. Molecular interaction studies have shown that Nirmatrelvir binds covalently with the catalytic triad of the active site of the viral protease enzyme (3CLPRO). It, therefore, acts by stopping the SARS-CoV-2 replication by its ability to block the translation of the viral genetic materials. Research studies conducted have proven the efficacy of this oral anti-viral drug in mild to moderate COVID-19 patients beside its ease of oral administration and good oral bioavailability. Alternative synthetic methods to scale up the synthesis of this potent molecule are needed to reduce the treatment cost of the COVID-19. Extensive clinical research on a larger group population is also underway for ensuring the safety and efficacy of this medication in the battle against the COVID-19 pandemic.