# Treatment Duration of Each Anti-COVID-19 Agent Used in a Tertiary Hospital in Japan

## TL;DR

This study compares the treatment durations of four anti-COVID-19 drugs in Japan and finds differences in how long each is used.

## Contribution

The study provides new clinical data on treatment durations of anti-COVID-19 agents in a Japanese hospital setting.

## Key findings

- All four anti-COVID-19 agents reduced viral antigen titers in patients.
- Treatment durations varied significantly among the four drugs, with remdesivir having the longest duration.
- The differences suggest varying anti-viral effectiveness in clinical practice.

## Abstract

Four anti-COVID-19 agents, nirmatrelvir/ritonavir (Nir/r), ensitrelvir (ESV), molnupiravir (MPV), and remdesivir (RDV), have been used in Japan for adult patients, and their clinical effectiveness, especially treatment duration and reduction of viral antigen titers, was investigated. A total of 114 adult cases received anti-COVID-19 treatment (33 Nir/r, 27 ESV, 24 MPV, and 30 RDV) in our hospital on admission, and the viral antigen titers were sufficiently decreased in all 114 patients. However, the treatment durations differed significantly: 4.09 days with Nir/r, 4.76 days with ESV, 4.74 days with MPV, and 5.08 days with RDV. These data suggest that the anti-viral activity of each anti-COVID-19 agent may differ in clinical use.