As GSK launches the respiratory syncytial virus (RSV) vaccine Arexvy in South Korea, it will challenge the market on a full-scale.

Arexvy is already expanding its market dominance in the global market with its strength as the first RSV vaccine. The company will likely focus on expanding vaccine awareness as it opens the RSV vaccine market for the first time.


On May 14, GSK Korea convened a press conference celebrating the launch of Arexvy, the world's first RSV vaccine. The company showcased a preventative strategy for seniors against RSV and Arexvy's clinical significance.

Arexvy received approval from the Ministry of Food and Drug Safety (MFDS) at the end of December 2024 for the 'Prevention of lower respiratory tract disease (LRTD) caused by RSV in adults over 60 years of age and older.'

Approval of Arexvy was based on results from two Phase 3 studies, 'RSV OA=ADJ-006' and 'RSV OA=ADJ-004,' involving adults 60 years of age and older.

The study results showed that during the first RSV season, Arexvy significantly lowered the RSV-LRTD risk by 82.6% and severe RSV-LRTD risk by 94.1% in participants 60 years of age and older compared to placebo.

Furthermore, the efficacy of the vaccine regarding RSV-A-associated LRTD increases and RSV-B-associated LRTD increases were 84.6% and 80.9%, respectively.

Dr. Ji-Yong Moon, Professor of Konkuk University's Department of Respiratory-Allergy and Clinical Immunology, explained, "RSV infection causes complications, such as pneumonia, in adults aged 60 years or older and it may require hospitalization or lead to death in severe cases," and added, "Based on a retrospective study, 56.8% of the hospitalized adults over age of 65 had pneumonia and 10.6% of those died."

Dr. Moon added, "Despite the high disease burden, awareness of RSV infection is poor, and differential testing is not well implemented, so the disease burden of RSV infection has been underestimated." He said, "RSV infection is as contagious as influenza, but there is no specific treatment other than supportive care, so prevention is most important."


Experts consider that the launch of the first RSV vaccine, Arexvy, is expected to be significant from a preventive standpoint. Professor Jacob Lee, Professor of the Division of Infectious Disease at Hallym University Kangnam Sacred Heart Hospital, reported that RSV vaccination is already recommended in the United States.

Dr. Lee said, "Arexvy showed a preliminary efficacy of 94.6% against RSV-LRTD in adults with one or more comorbidities," and emphasized, "Considering that 84% of domestic adults aged 65 and over have one or more chronic diseases, these data are noteworthy."

Dr. Lee stated, "Arexvy was approved in the U.S. in 2023, real-world data on its use have accumulated, and excellent preventive efficacy has been confirmed in actual clinical settings." He said, "The U.S. Advisory Committee on Immunization Practices (ACIP) recommends RSV vaccination for high-risk individuals aged 60–74 and all adults aged 75 and older."

Cost and awareness remain challenges… "NIP is necessary from a long-term perspective"

Regardless of the preventive value of RSV through Arexvy, it remains uncertain how much influence it will exert in the market.

Currently, Arexvy remains non-reimbursed in South Korea. Without a recommendation like that of the U.S. ACIP, there is a need to improve awareness.

In particular, the fact that the recommended vaccination age in the U.S. is higher at 75 years old, compared to the domestic approval age of 60 and over, also raises questions.

Regarding this, Dr. Lee explained, "In South Korea, the Korean Society of Infectious Diseases is expected to announce a recommendation within this year, but it is unlikely to differ significantly from the U.S.," and added, "To enter the National Immunization Program (NIP), sufficient disease burden research needs to be conducted."

Dr. Lee continued, "There is a cost burden and domestic data are lacking, but as the population structure changes, the number of vaccination targets will also increase. Through research data and cost-effectiveness, we can hope for RSV prevention through the NIP in the long term."

GSK Korea has stated that it will work to improve awareness through TV advertisements and other means alongside the launch of Arexvy.

Hyunji Kwon, Business Unit Head at GSK, added, "RSV is a disease with a great unmet medical need yet remains unfamiliar, so we will work to improve awareness among medical staff and high-risk patients," and added, "In a super-aged society in which, for the first time, the population in their 60s exceeds that in their 40s, we will collaborate with the medical community and the government to increase patient access."