IP Alerts

April 19, 2018

The Patent Trial and Appeal Board (PTAB) rarely grants a request for rehearing on a decision to institute inter partes review. But on April 9, in Incyte Corporation v. Concert Pharmaceuticals, the PTAB did exactly that. This decision provides some guidance for those in the position to seek rehearing before the PTAB.

In early 2017, Incyte Corporation filed a petition for inter partes review of a patent held by Concert Pharmaceuticals. The patent concerned a modified form of a specific chemical compound (ruxolitinib) said to be useful as a hair loss treatment. Incyte argued that the modified compound was obvious in light of several prior art publications. In its initial decision denying institution, the PTAB disagreed.

To determine whether a new chemical compound is obvious over the prior art, courts look to factors including (1) whether a chemist of ordinary skill would have selected the asserted prior art compounds as “lead compounds,” or starting points, for further development efforts, and (2) whether there is a reason to modify a lead compound to make the claimed compound with a reasonable expectation of success. In its petition, Incyte did not expressly provide a “lead compound” analysis. As such, the PTAB found that Incyte had failed to meet its burden to show why a chemist would have selected ruxolitinib as a lead compound over the hundreds of other compounds disclosed in the prior art. Additionally, the PTAB declined to accept Incyte's argument that a chemist would been motivated to modify ruxolitinib, because there was no express motivation in the prior art to do so.

Incyte filed a request for rehearing arguing that the PTAB had misapprehended the law and overlooked substantial evidence related to the lead compound analysis, the motivation to combine references, and the degree to which a person of ordinary skill in the art would have had a reasonable expectation of success. Incyte further argued that the PTAB erred in requiring an express motivation in the prior art to find a reason to modify ruxolitinib.

The PTAB granted Incyte's request for rehearing. The panel concluded that the decision denying institution had applied an overly restrictive standard for the lead compound analysis and for the reason to combine the cited references. Even though Incyte did not expressly conduct a lead compound analysis, the PTAB acknowledged that one of the prior art references specifically claimed ruxolitinib and another taught several “useful properties” of the compound. As such, the PTAB found that a person of ordinary skill in the art would have chosen ruxolitinib as a lead compound to make structurally similar compounds.

Reconsidering its prior conclusion on motivation to modify ruxolitinib, the PTAB concluded that it had previously misapplied the law by requiring an express motivation in the prior art to modify the lead compound. Instead, the PTAB held that the law does not require such express motivation and determined that “[p]etitioner can show a motivation to make deuterated ruxolitinib by demonstrating a person of ordinary skill in the art would have expected deuterated ruxolitinib to have ‘similar properties’ as ruxolitinib.” The PTAB concluded that Incyte had alleged a motivation to make deuterated ruxolitinib merely by demonstrating that a chemist would have expected the new compound to have similar properties as prior ruxolitinib.

Concert, the patentee, argued that even if there were a reason to modify ruxolitinib, there would be no reasonable expectation of success in producing the claimed compound. Concert further pointed to the alleged unexpected results of the compound. On these issues, the PTAB found that the parties had submitted competing testimonial evidence that raised a genuine issue of material fact that required resolution via the inter partes review proceeding.

While the PTAB seldom grants a request for rehearing on its decision to institute inter partes review, this decision seems to provide an avenue for raising such a request. If the PTAB has arguably misapplied the substantive law, it may be willing to grant the request for rehearing.

For more information on this decision, please contact Fitch Even partner Paul B. Henkelmann, author of this alert.

Fitch Even law clerk Evan Kline-Wedeen contributed to this alert.

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