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Plaintiffs say they overpaid for mumps vaccine for years

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Suit alleges violations of federal and state laws

By Mike Scarcella

WASHINGTON, Oct 20 (Reuters) - The U.S. Supreme Court

declined on Monday to hear a bid by a group of physicians and

healthcare providers to revive their antitrust lawsuit accusing

drugmaker Merck ( MRK ) of misleading federal regulators to

maintain a decades-long monopoly over the mumps vaccine market.

The justices turned away an appeal by the plaintiffs of a

lower court's decision to throw out the lawsuit on the basis

that the drugmaker was protected under a legal doctrine that

immunizes companies from antitrust claims based on actions aimed

at swaying government decision-making.

A collection of family doctors and physicians' groups from

New Jersey and New York filed the lawsuit in 2012 in federal

court in Philadelphia, seeking monetary damages.

The claims remaining in the long-running litigation involve

allegations that the plaintiffs were overcharged for New

Jersey-based Merck's ( MRK ) mumps vaccines as a result of the company's

monopolization of the mumps vaccine market in violation of

federal antitrust law and New Jersey and New York state laws.

The plaintiffs said that submissions by Merck ( MRK ) to the U.S.

Food and Drug Administration contained misrepresentations that

effectively boxed out competitors such as GlaxoSmithKline

and delayed market entry of a rival vaccine for more

than a decade.

Merck ( MRK ) made the only mumps vaccine in the United States from

1967 until 2022. It is sold as part of a combined vaccine

against mumps, measles and rubella, known as MMR-II.

The FDA in the 1990s raised concerns that the mumps vaccine

lost potency toward the end of its 24-month shelf life,

according to the lawsuit. The lawsuit accused Merck ( MRK ) of

misleading the FDA in the 2000s about the potency and efficacy

of the mumps vaccine. Merck ( MRK ) boosted the vaccine's initial

potency and submitted a supplemental application to the FDA to

continue selling it without revising its efficacy claims.

The so-called Noerr-Pennington doctrine at issue in the case

was established under a pair of Supreme Court decisions in the

1960s.

Merck ( MRK ) has denied any wrongdoing and has argued that its

communications with the FDA were legitimate regulatory

submissions protected by Noerr-Pennington immunity.

The Philadelphia-based 3rd U.S. Circuit Court of Appeals

found that Noerr-Pennington immunity is broad, though not

absolute. Actions intended to influence government

decision-making are not immune from liability if they are deemed

a "sham," it said. But it decided that even if Merck's ( MRK ) petitions

to the FDA contained falsehoods, they were not "sham" petitions

because they succeeded in obtaining the agency's approval.

In their request to the Supreme Court to hear their appeal,

the plaintiffs urged the justices to resolve what they said was

a split among federal appeals courts over whether alleged

intentional deception can fall outside Noerr-Pennington's

protections.

Merck ( MRK ) countered that the alleged misrepresentations did not

materially affect any statement on the vaccine label. The

company also said the FDA had taken no action to revise the

label despite being made aware of the allegations years earlier.