March 27 (Reuters) - Moderna ( MRNA ) said on Wednesday

it has entered into an agreement with private equity firm

Blackstone's life science investment platform for a

funding of $750 million to develop its mRNA flu vaccines.

The biotech firm has been developing multiple vaccines to

make up for a decline in sales of its COVID shots, sold under

brand name Spikevax, and plans to spend about $4.5 billion in

2024 towards research and development.

Developing multiple vaccines "requires substantial

investment in late-stage studies and we are excited to welcome

Blackstone and their innovative financing model," CEO Stéphane

Bancel said in a statement.

Blackstone Life Sciences will get commercial milestone

payments and low-single digit royalties as part of the

agreement, the COVID-19 vaccine maker said.

Shares of Moderna ( MRNA ) rose over 2% in premarket trading.

Moderna's ( MRNA ) flu shots have generated a stronger immune

response against all four A and B strains of the influenza virus

compared to traditional flu shots in a late-stage trial,

according to data released in September.

The company estimates flu vaccines to represent an about $7

billion market this year, and expects its scope to widen as new

shots become available. Moderna ( MRNA ) plans to file its application

with regulators this year.

Besides the flu shots, Moderna ( MRNA ) is also developing a vaccine

to prevent infections from respiratory syncytial virus (RSV), a

combination shot against flu and COVID-19, a second generation

COVID vaccine, and a cancer vaccine co-developed with Merck.

Its RSV vaccine is expected to be launched this year in the

United States.

(Reporting by Leroy Leo and Sneha S.K. in Bengaluru; Editing by

Shinjini Ganguli)