Moderna Inc (NASDAQ:MRNA) shares are trading lower after a longer-term trial analysis revealed a faster decline in the effectiveness of its experimental respiratory syncytial virus (RSV) vaccine.

Citing analysts’ comments, follow-up data from Phase 3 mRNA-1345 Trial At ReSViNET suggests the vaccine efficacy is declining faster than RSV vaccines from GSK Plc (NYSE:GSK) and Pfizer Inc (NYSE:PFE).

Citing two analysts, Reuters noted the data, posted ahead of a conference on RSV next week, that showed mRNA-1345 vaccine efficacy of about 63% after 8.6 months, from 84% at 3.3 months.

Also Read: GSK’s Competitive Edge, Surpasses Pfizer in Respiratory Syncytial Virus Vaccine Sales.

Pfizer’s vaccine efficacy went from 67% to 49% in 17 months, while GSK’s fell to 77% at 14 months from 83%, Reuters highlighted, citing a TD Cowen analyst.

Top-line data released a year ago showed that mRNA-1345 demonstrated vaccine efficacy of 83.7% against RSV lower respiratory tract disease.

In December, Moderna announced changes to its operating model to bring focus to its short- and long-term business goals.

The company is focused on driving continued sales of its COVID-19 vaccine and launching its Respiratory syncytial virus (RSV) vaccine in 2024, while also preparing to launch multiple products per year from 2025 forward. 

In July last year, Moderna submitted marketing authorization applications for mRNA-1345 with the European Medicines Agency, Swissmedic in Switzerland, and the Therapeutic Goods Administration in Australia. 

It has initiated the rolling submission process for a Biologics License Application to the FDA.

Price Action: MRNA shares are down 7.08% at $87.03 on the last check Friday.

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