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CAFC: Extrinsic Evidence Can Only Be Used Against You

In a nonprecedential opinion, the United States Court of Appeals for the Federal Circuit held that extrinsic evidence is great when it’s being used against you, bad if you try to use it to help your patent. The court stated that although extrinsic evidence cannot be used to supplement a non-enabling specification, such evidence can be used to show whether the specification is itself enabling. Pharmaceutical Resources and Par Pharmaceuticals v. Roxane Labs (07-1093). [1]

Pharmaceutical Resources and Par Pharma appealed a summary judgment of invalidity of U.S. Patent Nos. 6,593,318 [2] and 6,593,320 [3] for lack of enablement. The patents relate to stable flocculated suspensions of megestrol acetate [4] and methods for making such suspensions.

Bristol-Myers Squibb was the first company to develop and patent a liquid pharmaceutical composition of megestrol acetate and had a patent that taught that stable suspensions of megestrol acetate can be created but that the type and concentration of the surfactant in solution is critical to creating a stable flocculated suspension. The BMS patent disclosed only one stable flocculated suspension composition, combining megestrol acetate with polyethylene glycol as a wetting agent and polysorbate 80 as a surfactant.

When Par formulated a generic version of BMS’s patented product, it tried to design around the BMS patent by utilizing other surfactants and wetting agents. In developing its own product, Par discovered that flocculated suspensions of megestrol acetate could be formed using a much wider range of ingredients and concentrations, including other surfactants and wetting agents.

After Par sued Roxane, Roxane argued that the patents were invalid and unenforceable and moved for summary judgment of invalidity.

Claim 19 recites:

An oral pharmaceutical composition in the form of a stable flocculated suspension in water comprising: (a) megestrol acetate; (b) at least two compounds selected from the group consisting of polyethylene glycol, propylene glycol, glycerol, and sorbitol; and (c) a surfactant.

In reviewing the summary judgment, the court looked at eight factors relevant to the enablement analysis:

(1) the quantity of experimentation necessary, (2) the amount of direction or guidance presented, (3) the presence or absence of working examples, (4) the nature of the invention, (5) the state of the prior art, (6) the relative skill of those in the art, (7) the predictability or unpredictability of the art, and (8) the breadth of the claims.

Unfortunately, in this case the court started with the premise that Par sought extremely broad claims in a field of art that it acknowledged was highly unpredictable and therefore, Par had set a high burden that its patent disclosure must meet to satisfy enablement.

While the district court concluded that the claims “have an extraordinarily broad scope,” Par argued that the claims were not as broad as suggested because the hypothetical pharmaceutical formulator would start experimenting with the twenty-two surfactants that the United States Pharmacopoeia and National Formulary (USP-NF) has recognized and approved for use in oral pharmaceuticals in order to practice the invention. In addition, Par argues that the district court erred in assuming that the claims covered use of a surfactant in any concentration.

The Federal Circuit stated flat out:

The claims allow the choice of any surfactant in any concentration (with the exception that claim 1 of the ‘320 patent does not permit polysorbate as the surfactant if polyethylene glycol is the chosen wetting agent). The language of the claims and the specification both suggest that the claims encompass hundreds of possible surfactants. Further, the disclosure of the ‘318 and ‘320 patents list dozens of “suitable” surfactant genera beyond those listed by the USP-NF.

Moreover, nothing in the language of the claims limits the concentration of surfactant. The specification gives a preferred concentration range for only one surfactant, docusate sodium. To the extent that Par now suggests that an ordinarily skilled artisan would know that surfactant concentrations over 0.030% weight-per-volume would not work, it follows that a large part of the asserted claims’ scope is directed toward inoperative embodiments. The number of inoperative combinations is significant when assessing the experimentation that an ordinarily skilled artisan would need to practice the claimed invention

We thus conclude that the district court properly determined that the claims at issue “have an extraordinarily broad scope.” The district court also correctly noted in its analysis that our case law requires that the full scope of the claims be enabled.

In determining that the cited claims were not enabled, the court held:

Taking into account the broad scope of the claims and the highly unpredictable nature of the art, Par’s evidence regarding enablement fails to establish a genuine issue of material fact as to whether or not the claims are enabled and therefore fails to defeat summary judgment.

Par’s specification discloses only three working examples, utilizing only one new surfactant. Given the highly unpredictable nature of the invention and the extremely broad scope of the claims, these three working examples do not provide an enabling disclosure commensurate with the entire scope of the claims.

Thus, the court concluded that the patents are invalid under 35 U.S.C. 112 [5], first paragraph, for lack of enablement.