Vaccine Info

Xocova COVID-19 Antiviral

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Last reviewed
February 28, 2023
Fact checked by
Robert Carlson, MD

Xocova® COVID-19 Antiviral 2023

Xocova® (ensitrelvir fumaric acid, S-217622) is a therapeutic drug for treating people diagnosed with COVID-19. Xocova is a 3CL protease inhibitor created through joint research between Hokkaido University and Shionogi. Xocova suppresses the replication of SARS-CoV-2 by selectively inhibiting 3CL protease. 

Ensitrelvir is an investigational drug outside of Japan. In addition, the brand name Xocova® has not been approved for use outside of Japan and pertains only to the approved drug in Japan. According to non-clinical trials, Shionogi confirmed high antiviral activity against the Omicron virus variant, similar to other existing variants.

Shionogi & Co., Ltd. is located at 1-8, Doshomachi 3-chome, Chuo-ku, Osaka 541-0045, Japan.

Xocova Indication

Xocova® 125 mg tablet is an oral antiviral agent administered once daily for five days that suppresses the replication of SARS-CoV-2 coronavirus by selectively inhibiting the viral 3CL protease.

Xocova Availability 2023

A contract with the Japanese government to purchase 1 million courses of Xocova® 125 mg tablet became effective in 2022. It could be approved in South Korea and China in 2023.

Xocova News 2023

February 21, 2023 - Shionogi & Co., Ltd. presented further results from the Phase 3 part of the pivotal SCORPIO-SR trial (Phase 2/3 study) conducted in Japan, South Korea, and Vietnam of the novel COVID-19 oral antiviral ensitrelvir. Shionogi also presented exploratory data from the Study evaluating the potential effect of ensitrelvir on the symptoms of long COVID. 

November 22, 2022 - Shionogi & Co., Ltd. announced that Xocova® obtained emergency regulatory approval from the Ministry of Health, Labour and Welfare in Japan for the indication of SARS-CoV-2 infection. This approval was granted under the emergency regulatory approval system provided for in Article 14-2-2 of the Pharmaceuticals and Medical Devices Act.

March 25, 2022 - Shionogi & Co., Ltd. announced that Shionogi has entered into a basic agreement with the Ministry of Health, Labor and Welfare (MHLW) for the supply of S-217622 in Japan.

Xocova® Clinical Trials

The Phase 2b/3 part of the Phase 2/3 study targeting SARS-CoV-2 infected persons with asymptomatic/mild symptoms only is being conducted in Asia, mainly in Japan. With regard to safety, ensitrelvir was well tolerated, and there were no treatment-related serious adverse events or deaths in the study. The most common treatment-related adverse events were transient decreases in high-density lipoprotein and increases in blood triglycerides, as observed in previous studies. A global Phase 3 trial (SCORPIO-HR study 6 ) in non-hospitalized SARS-CoV-2 infected patients is ongoing. In addition, a global Phase 3 trial (STRIVE study 7 ) for hospitalized SARS-CoV-2 infected patients is scheduled to initiate soon. An onset prevention study for household members living with SARS-CoV-2 infected individuals and a pediatric study for children under the age of 12 are also in preparation.

July 26, 2021 - Shionogi initiated a Japanese Phase 1 clinical trial of the therapeutic agent S-217622 as an orally administered antiviral drug for COVID-19, caused by the novel coronavirus (SARS-CoV-2) infection, and the first dose was administered successfully on July 22. No safety concerns have been identified after the first dose.

September 28, 2021 - Shionogi initiated a Japanese Phase 2/3 clinical trial. The Phase 2/3 clinical trial will evaluate the efficacy and safety of oral administration of this drug once daily for 5 days in patients with mild COVID-19 or asymptomatic SARS-CoV-2 infection compared with placebo. 

January 31, 2022 - Shionogi presented results up to day 6 of Phase 2a part of a Phase 2/3 clinical trial of S-217622. The Phase 2b/3 part of a Phase 2/3 clinical trial is currently underway in mild, moderate, or asymptomatic COVID-19 patients.

Clinical Trials

No clinical trials found