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  1. U.S. appeal board rules GW Pharma’s method for CBD seizure treatment unpatentable.  
  2. Process suggests cannabis patents are being treated like other pharmaceutical IP. 
  3. Lack of published evidence is still a problem for many cannabis patents. 

Earlier this month, U.K.-based cannabis biopharma company GW Pharmaceuticals plc lost a court fight in the U.S. over whether some of its methods for treating seizures with high doses of cannabidiol are patentable.

As important as the decision itself is the manner in which the case occurred, according to Nicole Grimm, a partner with the Chicago law firm McDonnell Boehnen Hulbert & Berghoff LLP, which focuses on intellectual property.

In 2017, INSYS Development Company, INC., a competitor of GW, asked the U.S. Patent and Trademark Office (USPTO) to review GW’s patent on a method of treating seizures using 400 milligrams, or more, of CBD a day. The subsequent inter partes review by The Patent Trial and Appeal Board (PTAB) decided in favour of INSYS. GW’s two main claims were unpatentable, the board ruled in a written decision published on Jan. 3, although 11 “dependent claims” were allowed to stand, due to a lack of evidence from INSYS.

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The decision is a setback for GW, a clear leader in developing intellectual property for cannabis drugs (GW’s drug Epidiolex was the first cannabis-based medicine to be approved by the U.S. Food and Drug Administration). But the way the process was handled suggests that cannabis patents are starting to be treated like mainstream pharmaceutical patents, Ms. Grimm said – an important development for an industry moving rapidly into the legal mainstream.

"The patent office historically has been examining and granting patents on cannabis without any regard to the fact that it’s schedule I. But until you have these early opinions from the USPTO and the courts, there’s still a lot of uncertainty regarding enforcement and challenging these patents,” Ms. Grimm said.

"In issuing their decision, [the PTAB] did not take into account the fact that cannabis is Schedule I at all, so they treated this patent just like any other patent subject to an ITR challenge. That provides at least some clarity to cannabis patent owners, and potential third-party challengers, that this route is one way that people can challenge a cannabis patent," she added.

The manner in which GW’s patent claims were rejected, however, does highlight one persistent problem in patenting cannabis.

GW’s two main CBD treatment methods were not patentable, the PTAB decided, because when they were filed in 2010, other people with “ordinary skill in the art” (i.e. doctors or academics) could have come up with a similar treatment method based on existing published research.

There’s nothing unusual about this legal test being applied to a pharmaceutical patent. However, it shows how much judges rely on published evidence from the time a patent is filed in order to analyze its legitimacy.

“For patents on plants or a breeding method, certain aspects of the industry that have been around for a while but may not have been published, it can be difficult for patent examiners to find that information. And then you run the risk of having potentially overly broad patents being granted," said Ms. Grimm.

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