Itraconazole / Saperconazole – USA

On Jun 21 2019, Federal Circuit affirmed PTAB’s decision & found composition patent covering Mayne pharma’s antifungal drug invalid.

Mayne owns US 6,881,745 patent, which discloses and claims pharmaceutical compositions of azole antifungal drugs that are practically insoluble in aqueous media. Each claim at issue requires a pharmaceutical composition consisting essentially of about 100 mg of an azole antifungal drug and at least one polymer having acidic functional groups, wherein the composition exhibits certain pharmacokinetic properties in vivo. Specifically, claims 2, 9, 10, and 11 require that the in vivo composition provides a mean CMAX of at least 100 ng/ml, while claims 6, 12, 13, and 14 require a mean AUC of at least 800 ng.h/ml. Merck Sharp & Dohme Corp. (“MSD”) filed IPR for claims 1–3, 5–7, and 9–14 of the ’745 patent. The Board issued decision & finally held each of the challenged claims unpatentable.

On appeal Mayne argued that the Board erred in two respects: (1) by instituting review when the petition should have been found time-barred under 35 U.S.C. § 315(b) and (2) by declining to limit the claims to nontoxic compositions that produce the claimed pharmacokinetic profile in humans.

Mayne first raised its argument at institution, urging the Board to reject the petition because Merck & Co., Inc. (“MCI”) should have been identified as a real party in interest. Mayne also requested rehearing of the institution decision, arguing that the Board abused its discretion by failing to find the petition incomplete and time-barred. Mayne contends that the PTO’s clear and unambiguous rules provide that a petition can only be considered and accorded a filing date after all real parties in interest are identified. According to Mayne, because MCI was a real party in interest, the Board could not allow a correction without re-setting the petition’s filing date to the date of the amendment, which it did not do. Because MSD did not name MCI until December 14, 2017, more than a year after the service of Mayne’s complaint against it, Mayne maintains that the petition should have been time-barred. Federal Circuit, however,  sided with PTAB & said that the Board relied on “interests of justice” language in 37 C.F.R. § 42.5(c)(3), its late-action rule: “A late action will be excused on a showing of good cause or upon a Board decision that consideration on the merits would be in the interests of justice.” In applying § 42.5(c)(3), the Board did not plainly err in finding that MSD’s amendment would serve the interests of justice. Both MSD and MCI agreed to be bound by the estoppel effects flowing from the proceeding, and the Board found that it was properly apprised of conflicts relating to MCI from the identification of MSD. There was no evidence suggesting that MSD intended to conceal MCI’s identity. Conversely, unwinding the proceedings based on a strict view of the real-party-in-interest disclosure requirement would be at odds with the PTO policy expressed in § 42.1(b) that Part 42 “be construed to secure the just, speedy, and inexpensive resolution of every proceeding.”

Second, on the merits, Mayne argued to the Board that it should construe the claims as limited to nontoxic compositions that produce the claimed pharmacokinetic profile in humans. Mayne argues that the Board construed the term “pharmaceutical composition” too broadly to encompass toxic compositions that do not have any demonstrated beneficial therapeutic properties. MSD responds that the specification expressly discloses saperconazole as a “pharmaceutical composition,” but that extrinsic evidence indicates that saperconazole is toxic. Thus, in its view, the claims are not limited to non-toxic compounds. Federal Circuit agreed with MSD and the Board that the term “pharmaceutical composition” is not limited to nontoxic compositions. Because the specification is silent as to whether the claimed pharmaceutical composition is limited to being nontoxic, there is no basis to import such a limitation into the claim. Federal Circuit also said that extrinsic evidence also supports the Board’s construction.

Mayne next argued that the Board erred in failing to limit the claimed pharmacokinetic parameters to humans. In support of its position, Mayne cites the district court’s conclusion that “a person of ordinary skill ‘would immediately understand’ – given the results reported from administration of an about 100 mg dose – ‘that the claims of the ’745 patent are directed to humans only.’”  Federal Circuit agreed with MSD that the broadest reasonable interpretation of the claims is not limited to humans. The term ‘in vivo’ in general means, in the living body of a plant or animal. In light of this statement in the specification, a person of skill would understand the claims to include animals. Mayne further argued that, because the embodiment in the specification is from a human trial, the claims should be limited to humans. But Court said that it is improper to import a limitation from an embodiment into the claim. Accordingly, Court concluded that the Board did not err in its constructions of either “pharmaceutical composition” or the “wherein” clauses.

Therefore, Federal Circuit affirmed PTAB & held that Kai anticipates claims 2, 6, 9, 11, 12, and 14, and its combination with Sangekar and Babcock renders claims 2, 6, and 9–14 obvious.