Shionogi Enrolls the First Participant in Japan in its Global Phase 3 Trial of Ensitrelvir for the Preven

Shionogi & Co., Ltd. (Head Office: Osaka, Japan; Chief Executive Officer: Isao Teshirogi, Ph.D.; hereafter "Shionogi") today announced the first participant has been enrolled in Japan in its global Phase 3 study, Stopping COVID-19 pRogression with early Protease InhibitOr treatment Post Exposure Prophylaxis (SCORPIO-PEP). The study will evaluate the safety and efficacy of the novel COVID-19 oral antiviral ensitrelvir (Generic name: ensitrelvir fumaric acid, Code No.: S-217622, hereafter "ensitrelvir") for the prevention of symptomatic SARS-CoV-2 infection in study participants exposed to household contacts who are symptomatic and tested positive for SARS-CoV-2, when compared to placebo. The first participant is expected to be enrolled in the U.S. in July. In addition, Shionogi also announced that it has filed for full approval of ensitrelvir in Japan.

Ensitrelvir is an investigational oral antiviral that suppresses the replication of SARS-CoV-2 by selectively inhibiting the viral 3CL protease. Known as Xocova in Japan, ensitrelvir received emergency regulatory approval from the Ministry of Health, Labour and Welfare (MHLW) for the treatment of SARS-CoV-2 infection in November 2022. It remains an investigational drug outside Japan. In April 2023, ensitrelvir was granted Fast Track designation by the U.S. Food and Drug Administration.