By: Katherine Rubino

On January 3rd, 2019 the Patent Trial and Appeal Board (PTAB) issued a final decision in a first of its kind inter-partes review (IPR) pertaining to cannabis. The IPR was initiated by Insys Development Co., Inc. challenging U.S. Patent No. 9,066,920, entitled “Use of one or a combination of phyto-cannabinoids in the treatment of epilepsy. The ‘920 patent was assigned to GW Pharma Ltd.

IPR proceedings were enacted by the America Invents Act (AIA) and went into effect on September 16th, 2012. IPR offers one way to challenge a patent in lieu of litigation. IPR proceedings are utilized to review the patentability of one or more claims in a patent based on ⸹102 and ⸹103 challenges, including novelty and obviousness. IPR is more limited in that only patents or printed publications may be utilized to demonstrate that at least one claim is unpatentable as opposed to post-grant proceedings (PGR). IPR may not be filed until the later of nine months after a patent has been issued or after a PGR proceeding has terminated. The PTAB may grant an IPR petition when there is a reasonable likelihood that the petitioner will prevail as to at least one challenged claim. A final decision made in an IPR is able to be appealed to the Federal Circuit.

In the present IPR, Insys Development Co., Inc. (Insys) challenged to invalidate all 13 claims of GW Pharma Ltd.’s (GW) patent. Insys petitioned to invalidate GW’s patent on the basis of a ⸹102 challenge, based on three difference pieces of prior art, which included GW’s own published PCT applications.

The first two claims of the ‘920 patent were directed towards “a method of treating partial seizure comprising administering cannabidol (CBD).” The second claim was directed towards treatment of CBD in doses ranging between 400-800 mg. To note, Insys was the first company in the country to obtain approval by the Food and Drug Administration (FDA) for a drug product containing CBD. The drug, known as Epidiolex, was approved on June 25th, 2018 to treat seizure disorders.

In recent years, CBD has gained popularity both as the prescription drug product Epidiolex, and also in over the counter supplements. CBD has been used for a variety of conditions such as joint pain from Lyme disease, insomnia, gout, anxiety, depression, arthritis, and diabetes. CBD is different from tetrahydrocannabinol (THC) the main ingredient found in marijuana, as CBD is not psychoactive, and does not produce a high as THC does. Frequently, CBD is derived from hemp plants. Recently, on December 20, 2018 President Trump signed the Agriculture Improvement Act of 2018 into law, frequently also known as the Farm Bill. The major impact of the Farm Bill is that it legalizes the cultivation and sale of hemp derived CBD at the federal level. As legalized under the Farm Bill, CBD containing less than 0.3% THC is allowed to be sold, distributed, and produced in all fifty states.

In regards to the IPR petition, Insys argued that all 13 claims of GW’s patent were obvious because the first cited reference taught the treatment of epilepsy with CBD. Insys argued that a person of ordinary skill in the art (POSITA) would have found a dose of 400mg to be safe and effective based on available literature at the time. GW countered, arguing that CBD was an experiential treatment option and that a POSITA would have “no reasonable expectation that CBD would treat partial seizures at all.” After reviewing the available evidence, the PTAB found that claims 1 and 2 were obvious over two of the three asserted combinations of references. Both cited references described clinical studies that involved administering CBD to patients suffering from epilepsy.

After review of claims 1 and 2, the PTAB found that claims 3-13 were not obvious and thus remained valid in view of the three asserted references. The PTAB reasoned that Insys failed to meet its burden in proving obviousness of claims 3-13 in light of the cited references. The PTAB explained that Insys failed to identify where the limitations of claims 3-13 were found in the cited prior art.

This IPR is significant, in that the PTAB initiated the IPR and gave a final decision before the Farm Bill was passed and went into effect. At the time of this IPR, cannabis was still considered a Class I controlled substance, defined by the Drug Enforcement Agency (DEA) as “a drug, substance, or chemical with no currently accepted medical use and a high potential for abuse.” Other Class I substances include for example heroin, ecstasy, and peyote. This indicates a chancing atmosphere surrounding cannabis as more states move to legalize both medicinal and recreational use of cannabis. Further, this IPR is significant in that most of the ‘920 patent survived the challenge. At a time when around 70% of patents challenge in an IPR are invalidated, this case illustrates that strongly written claims, and a robust patent prosecution strategy can assist in later enforcement and validity of a patent.