CHAMPAIGN, Ill. ― Federal law requires every prescription drug to include a document describing dosing guidelines, contraindications, results from clinical trials and safety considerations. But a spate of recent court decisions has problematically treated that safety information in a drug's legally required package insert as key evidence in high-stakes patent cases against generic-drug manufacturers.
A new paper co-written by a University of Illinois Urbana-Champaign legal scholar argues that those decisions are incorrect and ought to be reversed by the U.S. Supreme Court in a forthcoming case.
Drug labels required by the U.S. Food and Drug Administration are intended to guide the safe and effective use of prescription drugs, but the overzealous and hyperbolic claims of patent infringement by drug companies is tantamount to "patent gamesmanship" that could potentially limit access to affordable generic drugs, said Jacob S. Sherkow, a professor of law and of medicine and an affiliate of the Carl R. Woese Institute for Genomic Biology at Illinois.
"It's a fallacy that doctors actually read these labeling documents that are required by the FDA," said Sherkow, the Richard W. and Marie L. Corman Professor of Law at Illinois. "Those lower court decisions, which embrace a legal theory we call 'infringement by label,' are incorrect. It's a fictional turn in the law that we hope the Supreme Court shuts down."
The paper, which was published by the New England Journal of Medicine, was co-written by Paul R. Gugliuzza of the University of Texas at Austin School of Law.
Although the FDA devotes substantial scrutiny to the textual content of drug labels, empirical evidence and clinical experience both suggest that physicians rarely rely on the information when treating patients.
By contrast, it is common practice for physicians to frequently prescribe medications "off label" on the basis of guidelines, peer-reviewed studies and clinical judgment, the scholars said.
"Clinicians usually rely on guidelines, experience and medical literature ― not legally required drug labels ― when making prescribing decisions," said Sherkow, also a professor at the Carle Illinois College of Medicine. "Yet courts have treated this federally mandated package insert text as sacrosanct and key evidence that's determinant of patent-infringement liability for generic drugmakers. It doesn't make a whole lot of sense."
When a generic-drug manufacturer seeks to enter the market, the patent owner may accuse the manufacturer of "inducing" physicians to use the generic drug according to the patented method, Sherkow said.
Disputes arise, in particular, when a company owns a patent not on the drug itself but on a particular method of using the drug ― for example, using it to treat one of several conditions.
"Typically, to show inducement, a patent owner must prove that the defendant 'encouraged, recommended, or promoted' a patented use," he said. "Manufacturers of brand-name drugs sometimes claim that content in a generic product's label constitutes such encouragement."
According to the paper, the theory of infringement by label turns a regulatory document ― one that many physicians don't routinely consult ― into a crucial piece of evidence in high-stakes patent litigation.
"By creating liability risk for generic-drug manufacturers that are complying with FDA rules, the current guidance from the lower courts hampers competition and could delay marketplace access to important medicines at a lesser cost," Sherkow said.
The risks are particularly acute for generic-drug manufacturers that refer to their product as "equivalent" to a brand-name counterpart ― as FDA law requires them to do, Sherkow said.
"We've had this law for 42 years now and it has produced good results," he said. "But we need to get back to a commonsense approach and away from litigation that threatens the public health importance of drug labeling."
The Supreme Court recently agreed to hear the case Hikma Pharmaceuticals USA v. Amarin Pharma, which involves a claim of infringement by label.
The court could use this opportunity to clarify that FDA-required labeling language, along with a generics manufacturer's straightforward statements about therapeutic equivalence, cannot alone prove patent infringement, the scholars said.
"The court's previous posture toward patent infringement cases is that there's nothing special about patent law, absent specific instructions from Congress," Sherkow said. "We believe this ought to present an easy case for the Supreme Court to adjudicate, and they should take the opportunity in Hikma to align patent law with clinical practice, FDA policy and traditional inducement principles. The court needs to course correct and reorient inducement toward a commonsense approach that makes clear that FDA-required labeling language, along with these rote statements about equivalence, is not patent infringement."
