The time to return-to-work in healthcare workers with COVID-19 treated with ensitrelvir, a novel oral inhibitor of 3C-like protease of SARS-CoV-2: An observational study utilizing pre-existing data from a single hospital
Makoto Katsuta, Masatoshi Kitazono, Naohito Nagai, Hiroto Karibe, Yusaku Takahashi, Yasuko Ariwa, Takuhiro Sonoyama, Tomoyoshi Yamaguchi
Journal of Infection and Chemotherapy, doi:10.1016/j.jiac.2025.102669
While treatment with anti-SARS-CoV-2 agents holds promise for managing healthcare workers with COVID-19, studies on this topic are limited. This study evaluated the time to return-to-work and remaining symptoms among healthcare workers with COVID-19 who received ensitrelvir and those who did not receive anti-SARS-CoV-2 drugs. This observational cohort study included healthcare workers diagnosed with COVID-19 between June and September 2023 at a single facility in Japan. Participants returned to work if they met all the following criteria: ≥5 days post-COVID-19 onset, fever resolution, and negative antigen test. The primary endpoint was the days from disease onset to return-to-work. We also evaluated the persistence of each symptom on the date of return-to-work, and the clinical and virological outcomes on the first scheduled date of return-to-work (Trial registration: UMIN000054128). The study enrolled 60 participants in the ensitrelvir group and 42 in the nonantiviral group. The mean number of days (SD) to return-to-work was 6.9 days (±1.6) in the ensitrelvir group and 7.7 days (±1.9) in the non-antiviral group. On the date of return-to-work, 4 participants in the non-antiviral group had taste disorders and 2 had smell disorders. On the first scheduled date of return-to-work (i.e. the date of first antigen test after onset), 56.7 % of participants in the ensitrelvir group and 33.3 % in the non-antiviral group had recovered, with the antigen test negativity in 76.7 % and 52.4 %, respectively. Ensitrelvir treatment for healthcare workers experiencing COVID-19 appeared to be associated with early symptom amelioration with viral load reduction, and shorter time to return-to-work.
Authorship statement Contributors M. Katsuta was the chief investigator and responsible for the organization and coordination of the trial. Y. Ariwa was responsible for the organization and coordination of the trial. Y. Takahashi was responsible for the data analysis. M. Katsuta, M. Kitazono, N. Nagai, H. Karibe and T. Yamaguchi contributed to the management or administration of the trial. T. Sonoyama and all authors developed the trial design and contributed to the writing of the final manuscript.
Declaration of competing interest Makoto Katsuda received a lecture fee from Shionogi & Co., Ltd., and Yusaku Takahashi, Yasuko Ariwa, and Takuhiro Sonoyama, are employees of Shionogi & Co., Ltd. All other authors report no potential conflicts of interest.
Appendix A. Supplementary data Supplementary data to this article can be found online at https://doi. org/10.1016/j.jiac.2025.102669 .
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