Preclinical discovery and development of nirmatrelvir/ritonavir combinational therapy for the treatment of COVID-19 and the lessons learned from SARS-COV-2 variants

Nirmatrelvir/ritonavir has a good tolerability profile. Its administration during the early stages of mild-to-moderate COVID-19 holds potential benefits, as it can help prevent the onset of an aberrant immune response that could lead to pulmonary and extra-pulmonary complications. However, its drug - drug interactions can be a factor limiting its use, at least in populations on some chronic therapies, along with the risk of infection relapse after treatment.