The mRNA vaccines against the Covid-19 pandemic have also shed light on the related technology as a next-generation vaccine for seasonal influenza. However, Korean companies remain cautious because of uncertain marketability, industry executives said Friday.

Global pharmaceuticals, including Moderna, Sanofi, Pfizer, and BioNTech, have begun clinical studies on mRNA flu vaccines to test their safety and efficacy. In addition, they expect to take a step forward to develop new flu vaccines using mRNA technology, preparing for future diseases after the lessons learned from the Covid-19.

However, most domestic drug makers capable of developing vaccines, such as SK Bioscience and GC Pharma, have remained researching related technologies but have not started developing them in earnest.

According to the World Health Organization, it takes five to six months for the first supplies of approved vaccines to become available once a new strain of influenza virus with pandemic potential is identified and isolated.

The preventive effect of flu vaccines depends on how accurately the products could prevent infection against the future epidemic virus following rapid production after development. In this vein, the mRNA vaccine is highly valued as a next-generation flu vaccine because of its quick response and mass production.

As mRNA vaccines produce antigenic proteins and forms antibodies in human bodies, they do not require a separate culture of pathogens, allowing companies to shorten the time needed for mass manufacture, the industry sources said. In addition, it has high safety as the injection does not include the virus, which also supported the technology as one of the mainstream products amid the rapidly spreading Covid-19 pandemic.

Encouraged by the interest in mRNA vaccines, some Korean companies initially showed interest in developing them but remained reluctant to put their interests into action.

Currently, SK Bioscience and GC Pharma can research to develop mRNA technology and make related flu vaccines.

SK Bioscience, which manufactures the world's first quadrivalent flu vaccine branded as SKYCellflu, has announced plans to expand its plant in Andong, North Gyeongsang Province, and build a new facility capable of producing mRNA vaccines by investing 150 billion won ($128 million).

The company can make vaccines cell culture, bacterial culture, genetic recombination, protein conjugation, and continued expanding investment in vaccine technology to solidify its position as a global vaccine production hub by preparing facilities for producing next-generation mRNA vaccines.

GC Pharma, which developed GC FLU quadrivalent, has launched a consortium to develop a domestic mRNA vaccine in June with Hanmi Pharm and ST Pharm.

Although the consortium initially is aimed to develop a homegrown Covid-19 vaccine, it appears that GC Pharma, which has already built facilities to produce end products, would use it as an opportunity to accumulate its technology, the sources said.

"Currently, our cGMP vaccine manufacturing plant with a production capacity of 400 million doses of the finished influenza vaccine is in operation," a GC Pharma official said. "In January last year, we built a plant for comprehensive manufacturing of our products in Ochang, North Chungcheong Province, as part of our plan made three to four years ago to win CMO deals for manufacturing biopharmaceutical products."