A biotechnology startup in southwestern Japan said Tuesday it will start human clinical trials for a drug to treat COVID-19 in 2021.

Bonac Corp., based in Kurume, Fukuoka Prefecture, said it has developed 72 candidates for nucleic acid medicines and tested their effectiveness against the respiratory disease caused by the novel coronavirus, in joint research with the Fukuoka Institute of Health and Environmental Sciences since June.

Ten of the candidates had proven to be effective in "significantly reducing the replication" of the virus, demonstrating the effectiveness of these medicines for COVID-19, according to the startup.

Supplied electron micrograph shows a new coronavirus that was first identified in central China's Wuhan city. (Photo courtesy of National Institute of Infectious Diseases, Japan)(Kyodo)

The research team has reduced the number of candidates from 10 to three that are highly stable in the human body and can be effective even in small quantities.

After selecting one of them through non-clinical tests, clinical trials involving human subjects will be launched next year.

The prospective drug could also be developed for treatment of Middle East respiratory syndrome, or MERS, and severe acute respiratory syndrome, or SARS, both of which are similar to COVID-19 and still have no treatments, Bonac said.

The startup, established in 2010, has said that by using its "RNA interference technology," it will attempt to create a drug that can decompose the genomic RNA of the coronavirus and induce antiviral effects in infected patients.

DNA and RNA, which are collectively called nucleic acids, can be found in the cells of all living organisms. Their tasks are to store and transmit genetic information.

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