La Cour d'appel fédérale examine la brevetabilité des plages de valeurs qui se chevauchent

In UCB Inc. v. Actavis Laboratories UT Inc., the Federal Circuit affirmed the district court’s judgement of invalidity on obviousness grounds but reversed the finding of anticipation. In reaching its decision on anticipation, the court rejected the district court’s application of the “at once envisage” rubric when the issue presented is whether a claimed range is anticipated by prior art disclosing an overlapping range. In reaching its decision on obviousness, the Federal Circuit upheld the district court’s application of the “blocking patents” doctrine.

The Patent at Issue and Neupro^® Product History

The patent at issue was U.S. Patent No. 10,130,589 (the ‘589 patent), assigned to UCB Pharma GmbH and LTH Lohman Therapie-Systeme AG (collectively, “UCB”). The patent is directed to “transdermal therapeutic systems comprising a solid dispersion comprising polyvinylpyrrolidone [PVP] and a non-crystalline form of rotigotine free base.”

The Federal Circuit treated claim 1 of the ’589 patent as representative (emphasis added):

1. A method for stabilizing rotigotine, the method comprising providing a solid dispersion comprising polyvinylpyrrolidone and a non-crystalline form of rotigotine free base, wherein the weight ratio of rotigotine free base to polyvinylpyrrolidone is in a range from about 9:4 to about 9:6.

Rotigotine is used to treat Parkinson’s disease. UCB’s transdermal rotigotine product (Neupro^®) was first marketed in 2007. The original Neupro^® product contained rotigotine and polyvinylpyrrolidone (PVP) at a 9:2 weight ratio. Several UCB patents described that formulation, including two Muller patents, U.S. Patent No. 6,884,434 (which claims transdermal systems having rotigotine in an amount effective for treating Parkinson’s disease and 1.5% to 5% w/w PVP), and U.S. Patent No. 7,413,747 (which claims transdermal systems with a weight ratio of 9% rotigotine to 1.5% to 5% PVP).

Shortly after the original Neupro® product was launched, it was discovered that when stored at room temperature, rotigotine was converted to a new crystalline form (“Form II”). Thereafter, UCB recalled the original Neupro^® product from the market (and also filed U.S. Patent No. 8,232,414 directed to Form II of rotigotine). In 2012, a reformulated version of Neupro^® containing rotigotine and PVP at a 9:4 weight ratio was approved by the FDA. The reformulated product is said to exhibit long-term stability at room temperature with a two-year shelf-life. The Muller patents were listed in the Orange Book for the reformulated Neupro^® product.

The District Court Litigation

In March 2019, UCB brought ANDA litigation against Actavis, asserting claims 1-3, 7, and 10-12 of the ‘589 patent. The district court held the claims invalid, finding that the Muller patents anticipated all asserted claims and that “the asserted claims would have been obvious in view of multiple prior art references, including the Muller patents.”

The district court’s anticipation determination was made under the “at once envisage” framework articulated in Kennametal, Inc. v. Ingersoll Cutting Tool Co., 780 F.3d 1376, 1381 (Fed. Cir. 2015). In Kennametal, the prior art disclosed a cutting tool assembled by combining different classes of materials and provided multiple options for each class. The claims at issue recited a specific combination of the materials. The Patent Office had held that the prior art anticipated each of the possible permutations disclosed, and the Federal Circuit affirmed. Applying Kennametal to the UCB claims, the district court reasoned that a person of ordinary skill reading the Muller patents would “at once envisage” a transdermal system with 9% rotigotine and 4% or 5% PVP (i.e., a ratio of 9:4 or 9:5), especially in view of the 9:3 ratio of Example 2 and the 1.5% to 5% PVP range in the claims.

As to obviousness, the district court additionally found that UCB had not shown that the claimed range was “an unexpectedly critical range, as opposed to an obvious adjustment after the appearance of Form II,” and that UCB had not established the nexus required to support patentability based on commercial success because the Muller patents have operated as blocking patents that discouraged competitors.

Décision de la Cour d'appel fédérale

The Federal Circuit decision was authored by Judge Stoll and joined by Chief Judge Moore and Judge Chen.

Anticipation of Overlapping Ranges

The Federal Circuit noted that “it is undisputed that the Muller patents disclose a range that overlaps with the claimed range,” and referred to precedent that “sets forth an established framework for analyzing whether a prior art reference anticipates a claimed range”:

The framework varies depending on whether the prior art discloses a point within the claimed range or discloses its own range that overlaps with the claimed range. If the prior art discloses a point within the claimed range, the prior art anticipates the claim. … On the other hand, if the prior art discloses an overlapping range, the prior art anticipates the claimed range “only [] if it describes the claimed range with sufficient specificity such that a reasonable fact finder could conclude that there is no reasonable difference in how the invention operates over the ranges.”

The Federal Circuit found the district had erred in using Kennametal to treat the case as a point-within-the-range case instead of an overlapping range case, noting that it had “rejected similar attempts to convert the disclosure of a range into the disclosure of individual values” in its 2015 decision in Ineos USA LLC v. Berry Plastics Corp. The Federal Circuit also emphasized that “Kennametal does not stand for the proposition that a reference missing a limitation can anticipate a claim if a skilled artisan viewing the reference would ‘at once envisage’ the missing limitation.” Instead, the Federal Circuit explained, “Kennametal addresses whether the disclosure of a limited number of combination possibilities discloses one of the possible combinations.”

The Federal Circuit therefore reversed the finding of anticipation.

Obviousness of Overlapping Ranges and Blocking Patents

On the other hand, the Federal Circuit found no error in the district court’s obviousness finding. The Federal Circuit agreed that Actavis had established a prima facie case of obviousness by showing that the claimed range overlaps with ranges taught by the Muller patents and that another prior art reference cited by UCB did not teach away. The Federal Circuit concurred with the district court finding that the improved stability was a difference in “degree” and a predictable effect of altering PVP content.

With regard to commercial success, the Federal Circuit agreed with the district court’s finding that the Muller patents “operated as blocking patents dissuading competitors from developing a rotigotine [transdermal system].” In so doing, the court summarized the blocking patents doctrine as follows:

In Merck and Galderma, we held that where market entry by others was precluded due to blocking patents, the inference of non-obviousness of the asserted claims from evidence of commercial success may be weak.

Considering the case before it, the Federal Circuit cited the district court’s findings that “UCB has held exclusive worldwide rights to rotigotine for all therapeutic indications since 1998,” and expert testimony that “the Muller patents would deter anyone other than UCB from developing the alleged invention in the ’589 patent.” The Federal Circuit said that it did not create a rule that treats “all co-owned patents as ‘blocking’ patents,” but rather correctly applied the principles to the specific facts at issue.

Thus, the Federal Circuit affirmed the district court’s finding of obviousness.

Overlapping Lessons

On the one hand, the Federal Circuit decision may be seen to favor patent owners by limiting application of Kennametal and the “at once envisage” rubric, and permitting patent owners to avoid anticipation by establishing that “the claimed range is critical to the operability of the claimed invention.” On the other hand, the decision reinforces the “blocking patents” doctrine, which can make it more difficult to support patentability of an improvement patent based on commercial success.