Japanese pharmaceutical firm Shionogi & Co. is considering developing a vaccine for the new Omicron variant of the novel coronavirus, one of its officials said Tuesday.

The Osaka-based firm official said Shionogi has already started preparations for manufacturing active ingredients that will be used as a base to develop the vaccine for the Omicron strain, which may be highly transmissible or pose an increased risk of reinfection to people who have previously caught the coronavirus.

A person gets a coronavirus vaccine shot in Osaka on Aug. 23, 2021. (Kyodo)

Concerns are growing over the Omicron variant with a large number of mutations, which was first reported to the World Health Organization by South Africa last week and has since been confirmed in a growing number of countries. Japan has yet to detect a case.

Shionogi is currently conducting a final clinical trial for its COVID-19 vaccine, aiming to bring it into practical use by March. It would be the first domestically produced vaccine for the respiratory disease caused by the virus.

The company is also developing an oral drug for patients with mild and moderate COVID-19 symptoms that would prevent them from worsening. It will speed up efforts to confirm whether the anti-viral drug will be effective for the Omicron variant as well, the official said.

Shionogi said earlier it is aiming to seek state approval for the oral drug by the end of this year, in the hope of offering at-home treatment. If approved, it would be the first oral drug for COVID-19 patients with mild cases in Japan.

"We will make preparations so that (our products) can respond to the Omicron variant," the official said, adding the company is placing priority on bringing its COVID-19 vaccine to the market.