Senju Pharmaceutical Co. Ltd. et al v. Apotex Inc. et al

Filing 129

MEMORANDUM ORDER dismissing without prejudice to renew 126 MOTION for New Trial or, Alternatively, to Amend Judgment and Findings Regarding Claim 7. IT IS FURTHER ORDERED that the record of this litigation is opened pursuant to Fed. R. Civ. P. 59(a)(2) so that the parties may present additional testimony with respect to the following specific questions regarding the validity of claim 7 of U.S. Patent No. 6,333,045 (the 045 patent). Order Setting Teleconference:( Telephone Conference set for 11/29/2010 03:00 PM before Judge Sue L. Robinson.). Signed by Judge Sue L. Robinson on 11/3/2010. (nmf)

IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE SENJU PHARMACEUTICAL CO. LTD., ) KYORIN PHARMACEUTICAL CO. ) ) LTD. and ALLERGAN, INC. ) Plaintiffs, ) ) v. ) ) APOTEX INC. and APOTEX CORP. ) ) Defendants. )

Civ. No. 07-779-SLR

MEMORANDUM ORDER

At Wilmington this1lday of November, 2010, having considered the materials in connection with plaintiffs' motion for a new trial or, alternatively, to amend the judgment

(0.1. 126; 0.1. 127; 0.1. 128);
IT IS ORDERED that plaintiffs' motion is dismissed without prejudice to renew. IT IS FURTHER ORDERED that the record of this litigation is opened pursuant to Fed. R. Civ. P. 59(a)(2) so that the parties may present additional testimony with respect to the following specific questions regarding the validity of claim 7 of U.S. Patent No. 6,333,045 (lithe '045 patent"). 1. Background. Plaintiffs are co-owners of the '045 patent, which is directed to aqueous liquid pharmaceutical compositions comprising gatifloxacin and disodium edetate, as well as various methods utilizing these compositions. Gatifloxacin is within the family of quinolones, which are broad spectrum antibacterial compounds that share a common core chemical structure. (See DTX 37 at col. 1:7-10; 0.1. 107 at 326-28) Briefly, plaintiffs brought this patent infringement action in response to multiple

Abbreviated New Drug Applications ("the ANDAs") filed by defendants. Plaintiffs alleged that the ANDAs infringed multiple claims of the '045 patent, including claim 7. 1 A bench trial was conducted from January 12 to January 14, 2010, and the court issued a memorandum opinion on June 14, 2010 to address the issues presented by the parties' post trial briefs.2 (See 0.1. 122) In the memorandum opinion, the court concluded that, inter alia, defendants had demonstrated, by clear and convincing evidence, that a 1989 article by Riley et al. ("the Riley reference"), in view of U.S. Patent Nos. 4,980,470 ("the '470 patent") and 4,551,456 ("the '456 patent"), rendered claim 7 of the '045 patent obvious. (Id. at
37~38)

a. The court predicated this conclusion of invalidity upon multiple findings of fact with respect to these prior art references. Specifically, the court found that the Riley reference proposed simulated solubility profiles for quinolone compounds. (Id. at 7) According to the Riley reference, quinolones with similar pKa values exhibit a
U~

shaped solubility curve with an inflection point about each of the pKa values. (Id.) The Riley reference further teaches that the addition of carboxylic acids of various molecular weights and structures to a quinolone solution maintained at pH 5 resulted in an increase in the solubility of the quinolone.

1Claim 7 claims [a] method for preventing precipitation of gatifloxacin crystals which comprises incorporating disodium edetate into an aqueous liquid preparation containing gatifloxacin or its salt. 2The reader is directed to the memorandum opinion for a more comprehensive understanding of the parties' positions in this litigation. See Senju Pharm. Co. Ltd. v. Apotex, Inc., Civ. No. 07-779-SLR, 2010 WL 2380735 (D. Del. June 14,2010). 2

b. The '456 patent discloses a quinolone ophthalmic solution comprising an aqueous solution of 0.3 wlv% of the prior art quinolone norfloxacin and 0.01 w/v% disodium edetate. Disodium edetate is disclosed by the '456 patent in a list of 8 excipients described as "conventional ingredient[s]" in ophthalmic compositions. ('456 patent at col. 2:5-10) The '470 patent, which discloses the compound gatifloxacin, explains that pharmaceutical formulations of gatifloxacin follow "the routes well known .
· · · f!

with respect to "oral[] and parenteral[] administration," including ".... liquids [and]

eye drops .... " ('470 patent at col. 7:21-26) c. The combination of these prior art references led the court to conclude that one of ordinary skill in the art would predict that gatifloxacin, having a pKa value similar to [prior art quinolones disclosed by the '456 patent], would likewise display a similar and predictable solubility profile