June 4 (Reuters) - Moderna ( MRNA ) convinced a U.S.

appeals court on Wednesday to uphold a ruling that undercut

patent infringement claims by biotech company Alnylam

Pharmaceuticals ( ALNY ) over Moderna's ( MRNA ) blockbuster COVID-19

vaccine Spikevax.

The U.S. Court of Appeals for the Federal Circuit upheld a

Delaware federal court's decision to interpret Alnylam's two

patents in a manner that foreclosed its infringement arguments.

Alnylam lost a similar dispute in a related Moderna ( MRNA ) case

last year. It has filed separate, ongoing patent lawsuits over

Pfizer's ( PFE ) COVID shots.

An Alnylam spokesperson said the company is reviewing the

Wednesday ruling and considering its options. A Moderna ( MRNA )

spokesperson said it was pleased with the decision and that its

vaccine was "a product of many years of pioneering mRNA platform

research and development."

Cambridge, Massachusetts-based Alnylam first sued Moderna ( MRNA )

and Pfizer ( PFE ) for patent infringement in 2022 for allegedly using

its lipid nanoparticle (LNP) technology in their vaccines to

deliver genetic material into the body. The lawsuits are part of

a web of patent disputes between biotech companies over COVID

shots, which includes a lawsuit filed by Moderna ( MRNA ) against Pfizer ( PFE )

later that year.

Moderna ( MRNA ) and Alnylam jointly agreed to dismiss Alnylam's

patent claims in the first case in 2023 after U.S. District

Judge Colm Connolly interpreted the patents to cover a type of

lipid that Spikevax did not have. A three-judge Federal Circuit

panel upheld Connolly's interpretation on Wednesday.

The case is Alnylam Pharmaceuticals Inc ( ALNY ) v. Moderna Inc ( MRNA ), U.S.

Court of Appeals for the Federal Circuit, No. 23-2357.

For Alnylam: Paul Hughes of McDermott Will & Emery

For Moderna ( MRNA ): Jeffrey Lamken of MoloLamken

Read more:

Alnylam files patent infringement lawsuits against Pfizer ( PFE ),

Moderna ( MRNA )

Alnylam to appeal ruling on patents related to Moderna's ( MRNA )

COVID vaccines

Moderna ( MRNA ) fends off Alnylam US patent lawsuit over COVID

shots, for now

(Reporting by Blake Brittain in Washington)