The ruling divided the court along familiar lines, with Chief Justice John Roberts and Justices Antonin Scalia, Anthony Kennedy and Samuel Alito joining Thomas in the majority.

Patient advocates argued that a decision shielding generic-drug companies would leave many injured people with little recourse. Generic drugs are used to fill 75 percent of U.S. prescriptions, according to the lawyers pressing the suit.

'Makes Little Sense'
Thomas said the court recognized that it “makes little sense” to bar suits against generic-drug makers while allowing cases against brand-name drugmakers. Mensing and Demahy would have been able to sue had they taken Reglan, the brand-name version of metoclopramide, he said.

“We acknowledge the unfortunate hand that federal drug regulation has dealt Mensing, Demahy and others similarly situated,” Thomas wrote. “But it is not this court's task to decide whether the statutory scheme established by Congress is unusual or even bizarre.”

The ruling leaves open the possibility that the Food and Drug Administration could change its regulations in a way that would open generic-drug companies to suits. Thomas's opinion relied on the agency's interpretation of its rules as barring those companies from unilaterally changing their warnings.

“As always, Congress and the FDA retain the authority to change the law and regulations if they so desire,” Thomas wrote.

'Absurd Consequences'
In dissent, Justice Sonia Sotomayor said the ruling “leads to so many absurd consequences that I cannot fathom that Congress would have intended to preempt state law in these cases.”

She said the ruling “could have troubling consequences for drug safety” by eliminating “the traditional state-law incentives for generic manufacturers to monitor and disclose safety risks.”

Justices Ruth Bader Ginsburg, Stephen Breyer and Elena Kagan joined Sotomayor in dissent.

The ruling “creates an absolutely untenable distinction in the law between name-brand and generic drugs,” said Louis Bograd, who argued the case on behalf of the women. “Three out of four patients in America have just lost the right to sue for inadequate warnings.”

Bograd, a lawyer with the Center for Constitutional Litigation in Washington, said that in some states patients who suffer injuries stemming from generic drugs may be able to sue the brand-name company that manufactured the original medicine. He said 1,000 lawsuits are pending over metoclopramide alone.

'Nail on the Head'
Mensing was suing privately held Actavis Group as well as units of Canonsburg, Pennsylvania-based Mylan and Petah Tikva, Israel-based Teva. Demahy was suing an Actavis unit.

Teva's lawyer, Jay Lefkowitz of Kirkland & Ellis LLP in Washington, said the court “hit the nail on the head today by making clear that federal law does not permit states to hold generic-drug manufacturers liable for using the very warnings federal law required of them.”

Actavis's chief executive officer, Doug Boothe, said the ruling “furthers meaningful consumer protection while also safeguarding against lawsuits that threaten the availability of safe and affordable pharmaceutical products by misconstruing the labeling responsibilities of generic manufacturers.”

The cases are Pliva v. Mensing, 09-993; Actavis Elizabeth v. Mensing, 09-1039; and Actavis v. Demahy, 09-1501.

www.bloomberg.com

Copyright 2018 Bloomberg. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.