Opinion ID: 2792379
Heading Depth: 3
Heading Rank: 2

Heading: the isv patents

Text: The ISV patents disclose various formulations and methods of using topical azithromycin as a gel eyedrop for treating eye infections. The claims essentially call for azalide (azithromycin) in a polymeric suspending agent for topical ophthalmic use. The district court concluded that none of the asserted claims of the ISV patents would have been obvious based on its finding that persons of ordinary skill in the art would not have been motivated to use the water-based polymeric solutions of the prior art in an azithromycin formulation because azithromycin was considered insoluble and unstable in water. See id. at . In addition, it found that were one to make a topical, water-based azithromycin formulation, one of skill in the art would not use polycarbophil, a gelling polymer, but would instead use a colloidal system. See id. The district court also found that many of the other limitations present in the claims were separately not obvious. See id. at . Finally, the district court found that the secondary considerations of unexpected results and long-felt need favored plaintiffs. Id. at . On appeal, Sandoz repeats its “framing of the obviousness question” argument and contends that it would have been obvious to use azithromycin to treat conjunctivitis and to formulate that treatment using DuraSite®, a commercial embodiment of Insite’s U.S. Patent No. 5,192,535 (the “’535 patent”), which lists a number of active ingredients, including erythromycin. According to Sandoz, it would have been obvious to replace erythromycin with azithromycin. It also contends that the ’411 patent itself is prior art to the ISV patents and that 14 INSITE VISION INCORPORATED v. SANDOZ, INC. Example 5 of the ’411 patent 2 discloses a water-based azithromycin formulation that renders the asserted claims obvious. Plaintiffs repeat their argument regarding the framing of the obviousness question and contend that the district properly determined that the ISV patents were not obvious. They argue that the ’535 patent is too general and lacked sufficient data to motivate a person of skill in the art to combine azithromycin with polycarbophil. They further contend that the expert testimony presented at trial supports the district court’s conclusion that the prior art taught away from the use of an aqueous polymer with azithromycin as recited in the asserted claims of the ISV patents. Plaintiffs also argue that Sandoz failed to show that a person of ordinary skill in the art would have been motivated to select a polymeric solution from among the number of choices available or would have had a reasonable expectation of success in making such a selection. Finally, Plaintiffs argue that the district court correctly held the asserted claims of the ISV patents are not invalidated by the ’411 patent. We have already addressed the framing of the obvi- ousness question in connection with our treatment of the ’411 patent, supra at 7–10. On the merits, we agree with the district court that Sandoz has not clearly and convincingly shown that the asserted claims of the ISV patents would have been obvious. Sandoz relies on the ’535 patent, which mentions the possibility that erythromycin could be combined with polycarbophil. The district court found, however, that the ’535 patent discloses a “laundry list of active ingredients” and credited the testimony of Dr. Lee that a researcher would focus on the 2 The heading for Example 5 is missing in the speci- fication of the ’411 patent. Example 5 is described from column 3 line 57 to column 4 line 2. INSITE VISION INCORPORATED v. SANDOZ, INC. 15 patent’s examples, none of which mention erythromycin. See Insite, 2013 WL 5975015, at . We see no clear error in the district court’s findings. See ’535 patent col.8 l.64–col.9 l.25 (listing numerous potential active ingredients). Sandoz argues that the district court’s treatment of the ’535 patent is inconsistent with Merck & Co., Inc. v. Biocraft Labs., Inc., which held that just because a “patent discloses a multitude of effective combinations does not render any particular formulation less obvious.” 874 F.2d 804, 807 (Fed. Cir. 1989). Sandoz overreads Merck. In Merck, one reference expressly taught the combination of the compounds claimed in the patent. Id. Here, by contrast, selecting from the laundry list of potential active ingredients listed in the ’535 patent at best teaches that polycarbophil can be combined with erythromycin. The ’535 patent does not mention azithromycin. Thus, the skilled artisan would still need to modify that combination by changing erythromycin to azithromycin. Moreover, as noted above, those of skill in the art would have been concerned about azithromycin’s solubility and stability in water, so the modification from erythromycin to azithromycin would be even less obvious. As for the admissibility of the ’411 patent as a reference against the ISV patents, we note that the ’119 application (which issued as the ’411 patent) was filed in 1998, before the earliest priority date of the ISV patents. The ’411 patent is assigned to Pfizer, while the ISV patents are assigned to Insite. The patents are not commonly owned or subject to a duty to assign to a common owner. Accordingly, the ’411 patent qualifies as prior art to the ISV patents under 35 U.S.C. §§ 102(e) and 103(c) (2006). The significance of the fact that these patents are not commonly owned, despite their being licensed to Inspire and listed in the Orange Book, may not have been fully appreciated by Sandoz’s expert, Dr. Reed, who said he was not basing his opinions on any post-1996 refer16 INSITE VISION INCORPORATED v. SANDOZ, INC. ences. Insite, 2013 WL 5975015, at . Be that as it may, the district court’s ruling that Dr. Reed was precluded from relying on the ’411 patent should not preclude Sandoz from relying on the ’411 patent itself as a reference, as it was listed by Sandoz in its pre-trial submission. And the district court, anticipating the possibility of appeal, took the precaution of analyzing whether the ISV patents were obvious over the ’411 patent. Id. It found that even in light of the ’411 patent, the claims of the ISV patents were not obvious. Id. at . We agree. The district court found the water-based examples of the ’411 patent to fall far short of satisfying Sandoz’s burden and found persuasive the testimony of Drs. Lee and Ahmed that the examples disclosing azithromycin and waterbased polymers raised concerns as to stability. The district court also found persuasive the testimony of Drs. Reed and Lee that there were significant differences between Carbopol disclosed in the ’411 patent and the polycarbophil of the ISV patents. We find no clear error in the district court’s fact-finding or the legal conclusion it drew therefrom on the obviousness question. Finally, we cannot say that the district court clearly erred in finding that there were meaningful secondary considerations. The district court found that a 60-fold increase in the concentration of azithromycin when dosed topically as opposed to orally was unexpected and also found that Azasite® met a long-felt need. Insite, 2013 WL 5975015, at , . Sandoz argues that some increase in concentration was to be expected. See Appellant’s Br. at 50. Even if true, Sandoz has not shown that a 60-fold increase was expected. Sandoz also offers nothing to rebut the district court’s finding that Azasite® met a longfelt need. In sum, we find that Sandoz has failed to clearly and convincingly show that the claims of the ISV patents would have been obvious. INSITE VISION INCORPORATED v. SANDOZ, INC. 17