Opinion ID: 809417
Heading Depth: 3
Heading Rank: 1

Heading: The “Independent Dissolution” Limitation

Text: The parties agreed that the limitation “dissolution of said naproxen occurs independently of said triptan” as recited in claim 1 of the ’183 patent means “[d]issolution of naproxen . . . and triptan from the multilayer tablet . . . occurs in the same amount of time ± 10% as when the same amount of naproxen . . . and triptan are given separately” as it was described in the patent specification. J.A.653; ’183 patent col.2 ll.48-54. Based on the evidence presented the district court found “Pozen has shown by a preponderance of the evidence the accused ANDA products achieve independent dissolution.” Pozen, 800 F. Supp. 2d at 811-12. Relying upon Par’s FDA filings and expert testimony presented at trial, the district court found that Par’s ANDA product performs the same function in the same way to achieve the same results and therefore satisfies the independent dissolution limitation under the doctrine of equivalents. Pozen, 800 F. Supp. 2d at 810. Pozen’s 27 POZEN INC v. PAR PHARMA expert noted that Par’s ANDA product was specifically formulated to achieve complete and independent dissolution. J.A.6029. Moreover, in its ANDA, Par represented to the FDA that the sumatriptan and naproxen in its ANDA product dissolves completely and independently from each other. J.A.157587; J.A.157602; J.A.158055. 12 The district court similarly found that DRL’s ANDA product achieves independent dissolution “by the way it formulates and manufactures the tablets.” Pozen, 800 F. Supp. 2d at 810. Relying upon the parties’ ANDA disclosures and expert testimony, the district court found that “substantially all the triptan is segregated and separated into the equivalent of a first distinct layer, in an equivalent side-by-side arrangement, and this achieves the result of independent dissolution.” Id. at 811. Moreover, the district court found “DRL’s testing of its ANDA product confirms its independent dissolution.” Id. 13 12 Par’s ANDA states: Most of our experiments were targeted to match the in-vitro dissolution profile of the individual brands. Naproxen Sodium, is poorly soluble in lower pH conditions, and tends to form a gel like matrix and thereby retard the release of co- administered drugs. Our primary objective is to develop a formulation having minimal effect of Naproxen Sodium over Sumatriptan Succinate dissolution, thereby having release profiles independent of each other in all the pH conditions. . . . J.A.157602. 13 Comparing DRL’s dissolution profile of its ANDA product to Table 7 in the ’183 patent, which shows the dissolution profile of sumatriptan in a bilayer tablet, Pozen’s expert, Dr. Williams, opined that the dissolution results in the table were almost the same as those in DRL’s ANDA product. J.A.6063-64. POZEN INC v. PAR PHARMA 28 Notwithstanding the evidence presented at trial, Appellants argue that Pozen did not prove independent dissolution because there is no evidence on the record that the comparison required by the ’183 patent was ever undertaken. Specifically, Appellants contend that there is no proof that the independent dissolution achieved by the ANDA products was compared to dissolution rates of the same amount of naproxen or sumatriptan alone. Appellants thus ask this court to find the district court erred by not requiring any proof that the active agents in their ANDA products achieved dissolution in about the same time (± 10%) it would take for either of the active agents to achieve dissolution when taken alone. The district court did not clearly err in finding infringement under the doctrine of equivalents because the record contains sufficient evidence that the independent dissolution requirement of the ’183 patent was met. In assessing equivalents, the court considers whether “the accused product[s] perform[] substantially the same function in substantially the same way with substantially the same result as each claim limitation of the patented product.” Crown Packaging Tech., 559 F.3d at 1312. Although there is no direct evidence comparing the rate of dissolution of the ANDA products to that of the agents individually, no such actual comparison was necessary. Under the doctrine of equivalents analysis Pozen need only show that the ANDA products performed the same function in the same way to achieve the same result as the claimed elements of the ’183 patent. Par and DRL provided expert testimony to show that the sumatriptan dissolves completely and independently from the naproxen and that the naproxen dissolves completely and independently from the sumatriptan in their ANDA products. Also, there is probative evidence from Par’s ANDA and comparison of DRL’s ANDA products dissolu29 POZEN INC v. PAR PHARMA tion profile showing that their sumatriptan and naproxen dissolve completely and independently from another. As a result, Appellants offer no basis for setting aside the district court’s finding. Indeed, there is sufficient evidence showing that logically if the agents dissolve in the same way they would if the other agent was not present, their dissolution takes the same amount of time it would taken when given separately. Thus, the district court did not clearly err in relying on Pozen’s expert testimony and concluding that Appellants’ ANDA products meet the “independent dissolution” limitation as recited in claim 1 of the ’183 patent under the doctrine of equivalents. 2. Infringement Of The “Substantially All” Limitation Claim 1 of the ’183 patent requires “substantially all of said triptan is in the first layer of said tablet and substantially all of said naproxen is in a second, separate layer.” ’183 patent col.18 ll.30-39. The district court construed this phrase as “at least 90%, and preferably greater than 95%, of the total triptan present in the tablet is included within one distinct layer and at least 90%, and preferably greater than 95%, of the naproxen present in the tablet is included within a second distinct layer.” Pozen Inc. v. Par Pharm., Inc., 719 F. Supp. 2d 718, 734 (E.D. Tex. 2010). It is undisputed that the first layer of Par’s ANDA tablet “contains 100% of the tablet’s sumatriptan, along with 15% of the tablet’s naproxen, with the remaining 85% of the naproxen in the second layer. DRL’s ANDA tablet has 100% of the tablet’s naproxen and 15% of the tablet’s sumatriptan in the first layer, with the remaining 85% of the sumatriptan in the second layer.” Pozen, 800 F. Supp. 2d at 809. POZEN INC v. PAR PHARMA 30
“substantially all” limitation The district court recognized that the claim construction of the term “substantially all” provided specific percentages but stated that “absent more limiting language in the intrinsic record” the doctrine of equivalents can be applied to find infringement where the accused value is insubstantially different from the claimed value. Id. (quoting Adams Respiratory Therapeutics, Inc. v. Perrigo Co., 616 F.3d 1283, 1292 (Fed. Cir. 2010)); see also U.S. Philips Corp. v. Iwasaki Elec. Co., 505 F.3d 1371, 1378 (Fed. Cir. 2007) (holding that despite a claimed concentration range the doctrine of equivalents can still be applied). Par argues that the district court improperly treated the claim term “substantially all” as a precise quantity entitled to the doctrine of equivalents when it is really a “fuzzy” quantitative limitation not entitled to equivalents. Par asserts that the word “substantially” was used to capture values lower than 100%, indeed the district court construed the term to include any amount as low as 90%, and Par contends Pozen should not reach below 90% “to encompass equivalents of equivalents.” Cohesive Techs., Inc. v. Waters Corp., 543 F.3d 1351, 1372 (Fed. Cir. 2008). DRL argues that the district court erred in granting Pozen a range of equivalency for the ’183 patent beyond the scope of equivalency determined through claim construction. DRL asserts that in the cases the district court cites the degree to which the accused product fell outside the specifically claimed range was miniscule in comparison to the amount their ANDA product falls outside of the claimed range. 14 Here, DRL contends, sumatriptan only 14 In Adams Respiratory the requirement was “at least 3500 units” and the accused product had 3493.38 31 POZEN INC v. PAR PHARMA makes up 85% of one layer; 5% less than the minimum 90% set forth in the construction of the term “substantially all.” Indeed, this court has stated that where “a patentee has brought what would otherwise be equivalents of a limitation into the literal scope of the claim, the doctrine of equivalents is unavailable to further broaden the scope of the claim.” Cohesive Techs., 543 F.3d at 1372. “[A]ll claim limitations are not entitled to an equal scope of equivalents. Whether the result of the All Limitations Rule, prosecution history estoppel, or the inherent narrowness of the claim language, many limitations warrant little, if any, range of equivalents.” Moore U.S.A., Inc. v. Standard Register Co., 229 F.3d 1091, 1106 (Fed. Cir. 2000) (internal citations omitted). However, although the claim language itself is a qualitative measure, the claim construction pulls directly from the specification to give the term “substantially all” a quantitative definition, specifically, “at least 90%, and preferably greater than 95%,” ’183 patent col.2 ll.62-65, and this court has previously concluded that the doctrine of equivalents is not foreclosed with respect to claimed ranges, see Adams Respiratory, 616 F.3d at 1291-92. In Kemin Foods, the court construed “substantially free from other carotenoids” to mean “significantly less than 10% of other carotenoids” based, in part, on the specification stating that “[g]enerally, the concentration of other carotenoids in the starting material should be 10% or less.” Kemin Foods, L.C. v. Pigmentos Vegetales Del Centro S.A. units, within 0.189% of the claimed minimum. Adams Respiratory, 616 F.3d at 1291. In Abbott Laboratories, the claim required between 68.8% and 94.5% by weight of a component, and the accused product had 95% of that component. Abbott Laboratories v. Dey L.P., 287 F.3d 1097, 1107 (Fed. Cir. 2002). POZEN INC v. PAR PHARMA 32 de C.V., 464 F.3d 1339, 1349 (Fed. Cir. 2006). The court determined that because Kemin did not argue that “significantly less than 10%” has a precise upper limit a reasonable person could determine that a concentration of 6.14%-9.86% does not infringe under the doctrine of equivalents. Id. Similarly, in this case, Pozen never stated that “at least 90%, and preferably greater than 95%” should be an absolute floor. Under the doctrine of equivalents a tablet layer with 85% of the agent can be fairly characterized as an insubstantial change from a tablet layer with 90% of the agent.
“substantially all” limitation under the doctrine of equivalents Turning now to the district court’s analysis of infringement of the “substantially all” limitation, we review the district court’s findings of infringement under the doctrine of equivalents for clear error. Conoco, 460 F.3d at 1357. The district court stated that the multilayer tablet claimed in the ’183 patent requires “substantially all of the naproxen and triptan [to be] segregated and separated for the purpose of independent dissolution.” Pozen, 800 F. Supp. 2d at 810. The parties’ experts agreed that the function was to have “separate, distinct layers of sumatriptan and naproxen. The way in which this function is achieved is by formulating the sumatriptan and naproxen in different manners to create physical barriers. The result is that substantially naproxen is separated from the [sumatriptan], thereby providing independent dissolution.” Id. The district court found that Par’s ANDA product performs essentially the same function, by segregating the naproxen and sumatriptan into two layers. Id. This is achieved by formulating them differently, specifically, by 33 POZEN INC v. PAR PHARMA using a polymer binder to form 15% of the naproxen into granules which are added to the sumatriptan layer. Id. The result is that one layer has 100% of the sumatriptan with 15% of the naproxen, and another layer has the remaining 85% of the naproxen, substantially all separated and segregated into two layers. Id. Therefore, the district court determined, Par’s ANDA product performs the same function, in the same way, and achieves the same result, and satisfies all of the limitations of the ’183 patent under the doctrine of equivalents. The district court also found that DRL’s ANDA product performs the same function of achieving separate, distinct layers by segregating the triptan and naproxen. Id. This is achieved by granulating 15% of the sumatriptan with a polymer binder and then spraying it on the naproxen which has been granulated with a polymer binder as well; the remaining 85% of the sumatriptan forms the other layer. Id. “Thus, substantially all the triptan is segregated and separated into the equivalent of a first distinct layer, in an equivalent side-by-side arrangement, and this achieves the result of independent dissolution.” Id. at 811. Therefore, the district court determined, DRL’s ANDA product performs the same function, in the same way, and achieves the same result, and satisfies all of the limitations of the ’183 patent under the doctrine of equivalents. Appellants argue that their ANDA products do not achieve separate distinct layers because one of the layers has both agents. However, their products contain a bilayer tablet, with 100% of one agent in one layer, and 85% of the other agent in the other layer. We determine, as the district court did, that this structure is insubstantially different from a bilayer tablet with 90% of the total therapeutic agent present in the tablet included in a single layer. POZEN INC v. PAR PHARMA 34 Appellants contend that their products are admixtures which Pozen specifically disclaimed during the ’183 patent prosecution. DRL argues that the district court improperly limited Pozen’s disclaimer to admixtures that achieve independent dissolution, when it really disclaimed admixtures in general. We agree that Pozen did in fact disclaim admixtures when it stated before the PTO: The present claims require that naproxen and [sumatriptan] be in a tablet in which they are seg- regated from one another in a “side by side ar- rangement” and in which their dissolution occurs independently of one another. The claims are lim- ited to one very specific tablet architecture. Among the dosage forms falling outside the claims are: admixtures; any dosage forms other than tab- lets; tablets in which one drug is in a core and surrounded by a layer or coating containing the second drug; and tablets containing multiple drug release pellets or microparticles. J.A.240667. However, the Appellants’ ANDA products are not admixtures, i.e. substances with blended or mixed ingredients, because substantially all of the agents are separated and segregated into two distinct layers, as explained above. Based on the evidence above, the district court did not clearly err in finding that Par’s ANDA products and DRL’s ANDA products met the “substantially all” limitation of the ’183 patent under the doctrine of equivalents.