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Brand Drugmakers’ Patents More Vulnerable Under Court Shift

Aug. 6, 2019, 8:41 AM

Generic drugmakers could have an easier time invalidating existing brand-drug patents that aren’t detailed enough under a recent appeals court opinion, according to lawyers watching the issue.

The precedential decision, Enzo Life Sciences, Inc. v. Roche Molecular Systems, Inc., by the U.S Court of Appeals for the Federal Circuit, signals that the court is looking for a new level of specificity in descriptions of inventions in patents.

The case addresses the issue of enablement, which is a requirement that the patent’s specification include enough detail for a person skilled in the given field to make or use the invention without undue experimentation.

The result could be that opportunistic generic drugmakers are more likely to challenge brand-name drug patents—even when they still have a long window of exclusive patent protection ahead of them, said Joe Edell, a Washington-based patent attorney with Fisch Sigler LLP.

“What’s at stake are the profits and the [research and development] that the drugmaker has put into developing these new drugs,” he said.

“For blockbuster drugs, even medium blockbuster drugs, companies stand to lose billions of dollars if the patents are invalidated for lack of enablement,” Edell added.

The most vulnerable patents will be recent ones—those for drugs that came to the market in the past 5-10 years—as they are more likely to include broad claim language, said Wayne Stacy, the chair of the intellectual property division at Baker Botts LLP in San Francisco.

“A lot of the drug patents are incremental improvements and they’re well described, but for the potential blockbuster type findings, you’re at the beginning of the discovery procedure, these are the type of cases that make those initial early research patents vulnerable,” he said. “It’s that cutting edge innovation that this case really jeopardizes.”


In Enzo, the Federal Circuit affirmed a holding that the company’s claimed invention—a method for labeling positions on a nucleotide—lacked enablement.

“The deficiencies in the description as to enablement cannot be cured in this case by looking to the knowledge of those skilled in the art at the time of the invention,” the court wrote.

In other words: Enzo’s patent was too vague and would have required an expert to perform tens of thousands of tests to duplicate or use the invention.

The court relied on its 2013 decision in Wyeth and Cordis Corp. v. Abbott Laboratories as the controlling opinion to reach its conclusion in Enzo on July 5.

In Wyeth, the Federal Circuit affirmed a grant of summary judgment and held the patent in question was invalid for lack of enablement because, again, it would have required “undue experimentation” for an expert in the field to make or use the invention.

“It comes down to two issues: How broad is your claim and how thorough is your disclosure?” Stacy said.

He noted the two decisions, taken together, send a message from the court about what it wants to see in drug patents.

“One case is an anomaly from the Federal Circuit, but when you start to see several cases, that signals a doctrine,” he said. “If they follow this line of thought, broader claims with broad specifications are in jeopardy.”

The Vulnerable Patents

It’s impossible to know how many drug patents could be affected, but it will be important for drugmakers to adapt as they draft new patents and not rely on theoretical assertions that are untested in the lab, said Karima Gulick, a patent lawyer and founder of Gulick Law in California.

“This case will set precedent for other drug patents where the claims cover thousands of different combinations and where these different combinations need to be tested,” she said. “But where a drug patent deals with unpredictable results, these patents will be vulnerable to invalidity.”

For example, some antibody drugs used to treat cancer could be vulnerable because they can have a lot of different permutations that are covered by the patent but haven’t been tested in the lab, Edell said.

The decision and narrower requirements that come with it also could force some drugmakers to wait longer until they’re further along in the development and testing process before they can apply for a patent for a new medication, Gulick said.

The case is: Enzo Life Sciences Inc. v. Roche Molecular Systems Inc., Fed. Cir., No. 2017-2498, 7/5/19.

To contact the reporter on this story: Valerie Bauman in Washington at

To contact the editors responsible for this story: Fawn Johnson at; Randy Kubetin at