Chinese drug developer Jiangsu Simcere Pharmaceutical Group said it is considering conducting overseas clinical trials on its oral COVID-19 prevention medicine, the company recently told the Global Times.

SIM0417, co-developed by Nanjing-based Simcere Group, the Shanghai Institute of Materia Medica and the Wuhan Institute of Virology under the Chinese Academy of Sciences, is a highly active small molecule candidate COVID-19 drug that targets the 3C-like protease, a key enzyme in the replication and life cycle of coronaviruses, including SARS-CoV-2.

Preclinical animal models have demonstrated good antiviral activity and the safety of SIM0417. Due to the 3CL protease's highly conserved nature, SIM0417 has a strong inhibitory effects on a variety of SARS-CoV-2 variants, including the highly infectious Delta and Omicron.

The company has been granted two approvals by the Chinese authorities to start clinical trials of the drug for its efficacy to treat COVID-19 and prevent the virus in people with a high infection risk. The approval for the drug's efficacy in preventing COVID-19 is the country's first of the kind, according to the company.

The immunity obtained following vaccination declines with time while the virus mutates. Therefore, the prevention effect of SIM0417 could be a good supplement to vaccines, Bao Jun, Board Secretary of the Simcere Group, told the Global Times.

According to Bao, the drug, within a certain period of exposure to a pathogen, could prevent the virus from copying at an early stage.

If SIM0417 goes to market, it will greatly reduce the workload of the health departments of having to manage close contacts, media reported.

If proven effective, the drug will be able to play a great role in the country's normal anti-epidemic work, Bao said.

The Simcere Group will select for the tests people who came in contact with infection cases within 48 hours, the firm previously told media. China's regular COVID-19 testing detects new infections very quickly and the sooner the prevention medicine is administered to close contacts the better.

US biomedical giant Pfizer tried to use its COVID-19 pill Paxlovid in post-exposure prophylaxis but was not successful. Paxlovid mainly targets the Delta variant and it is not as effective with the Omicron strain, media reported. Pfizer also used a contact period of 96 hours for the trials, which affected the final results.

The Simcere Group is also exploring the use of SIM0417 to treat COVID-19 patients. The Phase I clinical trials on the treatment finished in early June in the Qianfoshan Hospital, East China's Shandong Province.

Phase II clinical trials on patient treatment kicked off in Shanghai on June 13.

The Simcere Group also began preparations for mass production of the drug. A new production factory started construction in June in Nanjing. It is estimated that it will produce about 100 tons of the active pharmaceutical ingredients (APIs) that could be provided to about tens of millions of people, according to Bao.