Judge Richard Andrews recently issued his post-trial opinion in an ANDA case concerning a patent covering Glaxosmithkline’s (GSK) Avodart, a drug used to treat enlarged prostate. The defendants, several generic drug companies, stipulated to infringement but challenged the validity of the patent-in-suit on the basis of written description and enablement, as well as anticipation. Following a bench trial in January, Judge Andrews found that the defendants failed to prove any invalidity defense by clear and convincing evidence and, therefore, found in favor of GSK on all issues. Glaxosmithkline LLC v. Banner Pharmacaps, Inc., et al., C.A. No. 11-046-RGA, at 1-3 (D. Del. Aug. 9, 2013).
Judge Andrews first addressed the lack of written description defense. The patent-in-suit claimed both the pharmaceutical compound itself and pharmaceutically acceptable solvates thereof. The defendants argued that the solvates were not adequately described in the patent. Judge Andrews found that the specification need not “independently describe crystalline, precipitated, and reacted solvates as subgroups of the genus of pharmaceutically acceptable solvates” because the claim recited “pharmaceutically acceptable solvates” and there was “no reason why a person skilled in the art would not credit a patentee with possession of a solvate merely because the patentee did not disclose solvates formed by each [of the three] solvation process[es].” Id. at 7-10. Judge Andrews also rejected the defendants’ argument that the Court’s construction of “pharmaceutically acceptable” required the specification to “make clear that the claimed solvates are sufficiently soluble, have sufficient dissolution rates, are physically and chemically stable, and can be produced consistently.” Judge Andrews explained that this interpretation of his construction was too strict and could not be combined with the “high unpredictability as to how a particular solvate form will behave in a body” to require to the specification to provide “specific information as to acceptable solvate forms to ensure the inventors actually possessed the invention.” Id. at 12-13.
Judge Andrews then considered the lack of enablement defense. Judge Andrews found that the quantity of experimentation necessary given the state of the art was not unduly high, because the difficulties cited to by the defendants were difficulties associated with “commercialization of a finished drug product . . . rather than demonstrating how to make a safe solvate with therapeutic effect.” He explained that “finished drug products . . . need not be enabled by the patent.” This factor, along with the amount of direction provided by the patent-in-suit, the defendants’ admission that the level of ordinary skill in the art is very high, and the fact that solvates are well known in the art supported a determination that the claims of the patent-in-suit were enabled. Id. at 22-27.
The defendants also argued the Merck had independently invented the compound at issue and that the patent-in-suit was thus anticipated. The defendants based this argument on a lab notebook, compound data sheet, and article evidencing Merck’s experimentation. But the defendants did not have inventor testimony from anyone at Merck, and Judge Andrews found that there was no evidence that Merck had independently conceived of the invention. The Merck experimentation could not, therefore, serve as an anticipatory reference. Id. at 28-33.