Sept 23 (Reuters) - Moderna ( MRNA ) said on Tuesday its

updated COVID-19 vaccine formulation elicited a strong immune

response in all adults aged 65 and older, as well as in

individuals aged 12 to 64 with at least one underlying risk

condition.

Preliminary data from an ongoing post-marketing study

indicated that the vaccine, mNEXSPIKE, on average, showed

greater than a 16-fold increase in neutralizing antibodies

against the LP.8.1 variant - currently one of the Sars-CoV-2

variants under monitoring with increasing prevalence globally.

The trial was evaluating safety, tolerability and

immunogenicity of the 2025-2026 formula of mNEXSPIKE. The safety

profile of the vaccine was consistent with previous studies, the

company said.

Moderna ( MRNA ) is betting on its newer messenger RNA vaccines as it

grapples with waning demand for its original COVID-19 shot,

Spikevax, and lower-than-expected uptake of its respiratory

syncytial virus vaccine.

The U.S. Food and Drug Administration had approved mNEXSPIKE

in May, the first endorsement since the regulator tightened

requirements for COVID-19 vaccines and said it plans to require

new clinical trials for approval of annual boosters for healthy

Americans under age 65.

Spikevax is approved for individuals aged 65 and older, and

for those aged six months to 64 who are at risk for severe

disease.

The data for mNEXSPIKE follows additional preliminary

immunogenicity results for the 2025-2026 formula of Spikevax,

Moderna ( MRNA ) said.

Both vaccines for the 2025-2026 season "have demonstrated

strong immune responses against today's top circulating COVID-19

strains", the company said.