Moderna-Originated COVID-19 Vaccine Optimism, Too Early to Be Assured with Only Phase 1 Results

Side Effects Observed and Effectiveness Not Proven in Elderly
"Phase 3 Must Be Watched... Future Vaccine Supply Smoothness Also Key"

[Image source=Yonhap News]

[Asia Economy Reporter Minwoo Lee] The U.S. pharmaceutical company Moderna has achieved positive results in the early clinical trials of its novel coronavirus disease (COVID-19) vaccine. However, there are concerns that it is premature to regard this as a successful vaccine that will bring liberation from COVID-19. The success of Phase 1 trials is only at the dosage-setting level for entry into Phase 3, so the final success of the vaccine depends on the Phase 3 trials.

On the 18th, Kiwoom Securities viewed Moderna's Phase 1 trial success as positive but cautioned against complacency. Earlier, on the 14th (local time), Moderna published research results in the New England Journal of Medicine showing that all 45 subjects in the Phase 1 trial of its COVID-19 vaccine (mRNA-1273) developed antibodies.

According to the journal, Moderna divided 45 volunteers aged 18 to 55 into three groups based on vaccine dosage: 25 micrograms (㎍), 100㎍, and 250㎍. The vaccine was administered twice, followed by quarantine observation. After 28 days, antibodies were formed in all subjects. The 25㎍ group developed antibody levels similar to those of recovered COVID-19 patients about two weeks after vaccination, while the 100㎍ group showed antibody levels higher than those of recovered patients. Notably, at least eight individuals developed 'neutralizing antibodies' capable of inactivating the COVID-19 virus.

This sparked excitement in the industry, with related stocks soaring, as it was seen as a breakthrough in overcoming COVID-19. However, there are still factors to be confirmed. Huh Hyemi, a researcher at Kiwoom Securities, stated, "Although the neutralizing antibody levels in the 100㎍ dosage group are similar to or higher than those of recovered COVID-19 patients, it is still unknown whether these neutralizing antibodies provide protective immunity against COVID-19." She added, "The U.S. Food and Drug Administration (FDA) vaccine guidelines emphasize the importance of reducing severe disease by at least 50%."

Side effects have yet to be resolved. While no severe adverse reactions were reported, more than half of the participants experienced symptoms such as fatigue, headache, chills, muscle pain, and soreness immediately after vaccination. After the second dose, side effects appeared in 7 out of 13 participants in the 25㎍ group, 15 in the 100㎍ group, and 14 in the 250㎍ group, totaling 36 individuals. Among the 250㎍ group, three experienced severe reactions including fever, chills, headache, and nausea, with some cases reporting temperatures as high as 39.6 degrees Celsius.

The duration of immunity remains uncertain. Researcher Huh explained, "The formed neutralizing antibodies peaked at day 43 and decreased by day 57," indicating that regular administration may be necessary. She also noted, "This trial targeted individuals under 55 years old, but the elderly are the most affected by COVID-19," emphasizing that "the vaccine must be safe and effective without side effects in older adults."

With British pharmaceutical company AstraZeneca also expected to announce Phase 1 results on the 20th, there are forecasts that domestic pharmaceutical stocks could experience significant volatility. Researcher Huh commented, "In a situation where various academic conferences are not being held, investment sentiment in pharmaceuticals and biotech is heavily influenced by Phase 1 data," adding, "Phase 1 results are not sufficient to confirm vaccine success; we need to watch the Phase 3 results and also verify whether vaccine supply will be smooth in the future."

This content was produced with the assistance of AI translation services.