[Report] 'Guksan 1ho Corona Vaccine Production Site'... Stricter Quality Control with the Latest Technology

SK Bioscience Andong L House
First Production of 'Skycovione' Since Last Week
First Shipment Scheduled for the End of This Month

Using 2 of 9 Production Lines
Producing A and B Components Separately for Combination
Administered with Adjuvant

On the 10th, packaging work for the COVID-19 vaccine 'Skycovione' is being carried out at SK Bioscience L House in Andong-si, Gyeongbuk. (Photo by SK Bioscience)

[Andong=Asia Economy Reporter Lee Chun-hee] "Last week, we started the first production of ‘SKYCovione.’ Currently, 600,000 doses are being produced, and we plan to apply for national approval next week, with the first domestic shipment expected by the end of this month." (Sang-gyun Lee, SK Bioscience L House Plant Manager)

On the afternoon of the 10th, under heavy rain, we visited SK Bioscience L House in Andong, Gyeongbuk Province. This is the production site of the first domestically produced COVID-19 vaccine, ‘SKYCovione.’ To prevent external contamination, we changed into lab coats and wore shoe covers before entering the production facility. Inside, the smell of protein and the busy movements of staff managing vaccine production caught our attention.

L House is the largest vaccine factory in Korea, covering about 60,000 square meters with 9 production lines (suites) and a maximum annual production capacity of 500 million doses. When it was established in 2012, it was widely regarded as a ‘reckless gamble’ since there were no self-developed vaccines at the time. However, Vice Chairman Chang-won Choi of SK Discovery strongly pushed for the establishment of L House. It is known that Vice Chairman Choi emphasized, "Since we are putting our lives on the line anyway," and "Even if vaccine development succeeds, if production does not proceed, we will inevitably miss the timing." The ‘L’ in L House stands for ‘light.’ Together with the ‘S’ in SK Chemical’s Cheongju S House, which stands for ‘salt,’ it symbolizes the determination to lead essential pharmaceutical development as ‘light and salt.’

Since then, the company has succeeded in developing vaccines such as influenza and shingles, and added technological know-how like the ‘single-use’ bioreactor, which uses disposable plastic bags inside fermenters to reduce cleaning work, enabling rapid process development and scale-up. Through this, SK Bioscience has become a world-class facility with experience in producing three types of COVID-19 vaccines?AstraZeneca (AZ), Novavax, and SKYCovione?from drug substance (DS) to drug product (DP). Last year, it also received the European Union (EU) Good Manufacturing Practice (GMP) certification. Although the U.S. cGMP certification is still pending, the plant manager expressed confidence, saying, "We consider EU GMP and cGMP to be largely similar," and that it is fully achievable.

On the 10th, quality control (QC) of the COVID-19 vaccine 'Skycovione' is being conducted at SK Bioscience L House in Andong-si, Gyeongbuk. (Photo by SK Bioscience)

Currently, among the 9 suites, two suites?1 and 4?are used for SKYCovione production. Each suite has a different role. Suite 1 produces the antigen protein ‘component A’ using Chinese Hamster Ovary (CHO) cells, which are animal cells. Suite 4 produces ‘component B’ using Escherichia coli bacteria, and the two components are combined to create the drug substance. Since the cultivation methods differ, the facilities are separated for production.

This production method is because SKYCovione is a synthetic antigen vaccine applying the latest ‘nano particle’ technology. It is a technology that promotes the activity of antibody-producing cells through ‘self-assembly,’ where proteins autonomously assemble into various structures. This is why SK Bioscience President Jaeyong Ahn emphasized that it is "the world’s first vaccine applying computationally designed antigen."

The produced vaccine drug substance undergoes rigorous quality control (QC) procedures. In addition to the antigen titer, which is the core of efficacy, safety evaluations such as foreign substance detection and toxicity are conducted since it is administered to healthy individuals. The strict QC process is nerve-wracking, as any batch exceeding the allowable limits is entirely discarded. QC Analysis Team 1 Leader Juseop Lee said, "Because the A and B components are combined in a new way, QC is inevitably more stringent," and added, "QC procedures are being conducted day and night, including holidays, to meet the shipment deadline at the end of this month."

In the final drug product manufacturing process, packaging was being carried out rapidly. The SKYCovione vaccine is packaged together with GlaxoSmithKline (GSK)’s adjuvant ‘AS03,’ which is used to enhance immunogenicity. At administration, 10 doses of SKYCovione in a vial are mixed with 10 doses of AS03, and 0.25 mL of each is combined to inject a total of 0.5 mL per dose. To accommodate this administration process, the SKYCovione vials are produced with some extra space. The plant manager explained, "Currently, the initial production of 600,000 doses is underway," and "We are producing and storing excess drug substance to respond to additional orders."

On the 10th, packaging work for the domestic COVID-19 vaccine 'Skycovione' is being carried out at SK Bioscience L House in Andong-si, Gyeongbuk. / Photo by Lee Chun-hee

However, even if SKYCovione is shipped, it is currently only authorized for the primary 1st and 2nd doses for adults domestically. Therefore, the company is conducting additional clinical trials to obtain approval for booster doses and vaccination for children and adolescents. Overseas, approval applications have been submitted to the UK and the European Medicines Agency (EMA), and preparations are underway for listing on the World Health Organization (WHO) Emergency Use Listing (EUL).

It has also shown efficacy against the Omicron variant. An extended clinical study analyzing the cross-neutralizing ability of the booster dose confirmed immune responses against BA.1. Approximately seven months after the primary vaccination, the booster dose increased neutralizing antibody titers against Omicron by about 25 times compared to immediately after the second dose, and about 72 times compared to just before the booster.

SK Bioscience is also expanding the Andong L House. A site of about 100,000 square meters, 1.5 times the size of the existing L House, has been secured right next to it. By diversifying platforms such as messenger RNA (mRNA), the company aims to make it a ‘global vaccine production hub.’ Along with the Incheon Songdo Research and Process Development (R&PD) Center to be established in 2024, this is planned to be the core of SK Bioscience’s new growth strategy, ‘SKBS 3.0.’

Andong=Reporter Lee Chun-hee spring@