Case name: Almirall, LLC v. Torrent Pharms., Ltd., Civ. No. 20-1373-LPS (D. Del. July 13, 2021) (Stark, J.)
Pharmaceutical product and patent (s) on suit: Aczoneยฎ Gel, 7.5% (dapsone); US Patent No. 9,517,219 ("the '219 patent")
Nature of the case and question (s) presented: In August 2020, Torrent sent a notification letter to Almirall regarding ANDA's submission of Torrent to the FDA for permission to market a generic version of Almirall's Aczone Gel. Torrent's ANDA contained a โParagraph IVโ certification that the '219 patent was invalid and / or had not been infringed by Torrent's ANDA product. Almirall sued Torrent under 35 USC ยง 271 (e), alleging that Torrent's proposed ANDA product infringed the '291 patent. Once the allegations were closed, Torrent presented a motion for judgment on the allegations regarding his non-infringement counterclaim. He argued that his proposed formulation could not be in violation literally because it did not contain an ingredient required by the '291 patent claims, and was not in violation under the doctrine of equivalents because the estoppel doctrine of argument-based prosecution history applied. The court agreed with Torrent and granted his motion for judgment of non-infringement of the allegations.
Why did Torrent prevail: The claims of the '219 patent required that the pharmaceutical compositions have "a polymeric viscosity improver comprising acrylamide / sodium acryloyldimethyltaurate copolymer" ("A / SA"). But the formulation proposed by Torrent did not contain A / SA. Instead, Torrent's ANDA product contained type C carbomer homopolymer, also known as "Carbopol." Almirall apparently admitted that there was no literal infringement, but proceeded to a theory of infringement under the doctrine of equivalents.
Torrent argued that Almirall delivered Carbopol as an equivalent to A / SA during the prosecution and was therefore prohibited from asserting equivalents under the estoppel doctrine of argument-based prosecution history. The court explained: "[a]The argument-based prosecution history impediment prohibits a patent owner from asserting equivalents for a claim item when that assertion contradicts statements made to the patent examiner in the course of obtaining the patent. "
In this case, the court found that Almirall "clearly and unequivocally" turned over Carbopol as an equivalent to A / SA when it argued the following during the prosecution of a parent patent:
The present claims mention a new dapsone formulation in which the active ingredient is about 7.5% w / w dapsone and a completely new thickening agent is employed. The new formulation of the present claims does not include a carbomer such as Carbopolยฎ., but instead use like [sic] Acrylamidelsodium acryloyldimethyl taurate copolymer, also known as "Sepineo โข P 600", and in a much higher concentration (about 2% to about 6% w / w) compared to what Garrett teaches for their thickening agent.
The court explained that it was appropriate to consider the prosecution history of the main patent because the elements of the disputed claim were almost identical in both patents and because during the prosecution of the '219 patent, the application expressly adopted the arguments presented during the prosecution. of the main patent. and expressly repeated the previous argument. Furthermore, the applicant repeatedly referred to A / SA as the "sole thickener" or the "sole thickening agent". In holding that these statements met Carbopol's high standard of โclear and unmistakableโ delivery as equivalent to A / SA, the court stated โ[i]It's hard to imagine a clearer disclaimer from Carbopol than '[t]The new formulation of the present claims does not include a carbomer like Carbopol. "Almirall could not offer any persuasive argument that the above statements meant anything other than what the words clearly said. Instead, Almirall simply held that he had the right to be discovered before the court passed judgment The court disagreed, stating that Almirall had not made a plausible allegation of infringement and therefore had no right to be discovered.
Almirall argued that the court should deny the motion because another Delaware District judge denied a similar Rule 12 (c) motion from a different generic pharmaceutical company in a case involving the same NDA for Aczone Gel. The court refused because: (i) the courts have the discretion to deny the motions in Rule 12 (c); and (ii) the facts of the other case were not so straightforward: the generic complainant used a "multicomponent polymeric viscosity builder" in his proposed formulation, and thus the infringement case presented more difficult questions that would benefit from the discovery of facts and experts.
