The opinion of the court was delivered by: Greenaway, Jr., U.S.D.J.
This matter comes before the Court on the application for a preliminary injunction by Plaintiffs Aventis Pharmaceuticals, Inc., Merrell Pharmaceuticals Inc., Carderm Capital L.P., and AMR Technology, Inc. (collectively "Plaintiffs"), seeking to enjoin Defendants Barr Laboratories, Inc. ("Barr"), Teva Pharmaceuticals USA, Inc. ("Teva"), Ranbaxy Laboratories Limited and Ranbaxy Pharmaceuticals, Inc. (collectively "Ranbaxy"), and Amino Chemicals, Ltd. ("Amino") (collectively "Defendants"), from patent infringement, or inducing patent infringement, by marketing, making, using, or selling generic fexofenadine. For the reasons set forth below, the application for a preliminary injunction is denied.
This dispute concerns patents owned by, or licensed to, Aventis Pharmaceuticals, Inc., Merrell Pharmaceuticals Inc., Carderm Capital L.P., and AMR Technology, Inc. relating to fexofenadine formulations sold in the United States by Aventis under the tradename ALLEGRA(r). This antihistamine allergy medication product has achieved substantial commercial success in the United States. Between May 2001 and June 2002, Defendants Barr and Teva each filed Abbreviated New Drug Applications ("ANDA") seeking the Federal Drug Administration's ("FDA") approval to market generic drug products containing the same active ingredient, fexofenadine hydrochloride ("fexofenadine"), as ALLEGRA(r). In response, Plaintiffs filed a series of suits for infringement of a larger group of patents than is at issue in this motion for a preliminary injunction; litigation in these suits is ongoing.
On August 31, 2005, the FDA approved Barr's ANDA no. 076191. On September 1, 2005, the FDA approved Teva's ANDA no. 076447. On September 6, 2005, Barr and Teva announced an agreement to market generic fexofenadine jointly. Ranbaxy has manufactured fexofenadine for Barr. Amino has manufactured fexofenadine for Teva.
On September 20, 2005, Plaintiffs asked this Court to order Defendants to show cause why a preliminary injunction against Defendants should not issue. Plaintiffs sought for this Court to enjoin Defendants Teva and Barr from marketing generic fexofenadine, thereby actively inducing infringement of U.S. Patent No. 6,037,353 (filed Mar. 2, 1995) (the "'353 patent"), U.S. Patent No. 6,187,791 (filed Jan. 12, 2000) (the "'791 patent"), and U.S. Patent No. 6,399,632 (filed Sept. 15, 2000) (the "'632 patent") (collectively "the method patents"), and to enjoin Defendants Barr, Teva, Ranbaxy and Amino from making, using, or selling generic fexofenadine, thereby infringing claim 7 of U.S. Patent No. 5,750,703 (filed Feb. 2, 1995) (the "'703 patent" or "process patent"). On September 29, 2005, this Court granted the application and ordered Defendants to show cause why the preliminary injunction should not issue.
Subsequent to the filing of the application for the preliminary injunction, Plaintiffs stated that Barr has not put any fexofenadine manufactured by Ranbaxy on the market, beyond having made a token sale. Plaintiffs have not, however, withdrawn their application for a preliminary injunction against Barr or Ranbaxy.
APPLICABLE LEGAL STANDARDS
I. Preliminary Injunction
As the moving party, a plaintiff "is entitled to a preliminary injunction if it shows: (1) a reasonable likelihood of success on the merits of its claims; (2) irreparable harm if an injunction is not granted; (3) a balance of hardships tipping in its favor; and (4) the injunction's favorable impact on the public interest." Gillette Co. v. Energizer Holdings, Inc., 405 F.3d 1367, 1370 (Fed. Cir. 2005). In order to demonstrate a likelihood of success on the merits on a particular claim of patent infringement, Plaintiffs must show that, in light of the presumptions and burdens that will inhere at a trial on the merits, (1) Defendants likely infringe the patent, and (2) the claims of the patent will likely withstand Defendants' challenges to validity. Id. If Defendants "raise a substantial question concerning either infringement or validity, i.e., assert an infringement or invalidity defense that the patentee cannot prove 'lacks substantial merit,' the preliminary injunction should not issue." Amazon.com, Inc. v. Barnesandnoble.com, Inc., 239 F.3d 1343, 1350-1351 (Fed. Cir. 2001). Thus, once the non-movant has raised a substantial question as to infringement or validity, for the preliminary injunction to issue, the movant must prove that this question lacks substantial merit.
"[I]nfringement and validity analyses must be performed on a claim-by-claim basis." Id. at 1351. "[I]n cases involving multiple patent claims, to demonstrate a likelihood of success on the merits, the patentee must demonstrate that it will likely prove infringement of one or more claims of the patents-in-suit, and that at least one of those same allegedly infringed claims will also likely withstand the validity challenges presented by the accused infringer." Id.
The test for patent infringement requires a two step analysis: "the claim scope is first determined, and then the properly construed claim is compared with the accused device to determine whether all of the claim limitations are present either literally or by a substantial equivalent." Id. "To prove direct infringement, the plaintiff must establish by a preponderance of the evidence that one or more claims of the patent read on the accused device literally or under the doctrine of equivalents. Literal infringement requires that each and every limitation set forth in a claim appear in an accused product." Cross Med. Prods., Inc. v. Medtronic Sofamor Danek, Inc., 424 F.3d 1293, 1310 (Fed. Cir. 2005) (internal citations omitted). Although claim construction is an issue of law, the determination of infringement is a question of fact. Pause Tech. LLC v. TiVo Inc., 419 F.3d 1326, 1329 (Fed. Cir. 2005).
In Amazon, the Federal Circuit stated the standard for a validity challenge in the context of an application for a preliminary injunction:
Validity challenges during preliminary injunction proceedings can be successful, that is, they may raise substantial questions of invalidity, on evidence that would not suffice to support a judgment of invalidity at trial. The test for invalidity at trial is by evidence that is clear and convincing. . . . In resisting a preliminary injunction . . . one need not make out a case of actual invalidity. Vulnerability is the issue at the preliminary injunction stage, while validity is the issue at trial. The showing of a substantial question as to invalidity thus requires less proof than the clear and convincing showing necessary to establish invalidity itself. . . . When moving for the extraordinary relief of a preliminary injunction, a patentee need not establish the validity of a patent beyond question. The patentee must, however, present a clear case supporting the validity of the patent in suit.
Amazon, 239 F.3d at 1358-1359 (citations omitted).
I. Plaintiffs have not Demonstrated a Likelihood of Success in Eestablishing that Barr has Infringed the Process Patent
For purposes of the motion for a preliminary injunction, Plaintiffs assert only claim 7 of the '703 manufacturing process patent. There is no dispute that Ranbaxy has manufactured fexofenadine for Barr. Plaintiffs contend that Ranbaxy has infringed claim 7 of the '703 patent. Under 35 U.S.C. § 271(g), if Ranbaxy has infringed, Barr is liable as an infringer for importing Ranbaxy's product.
The parties agree that determination of Barr's and Ranbaxy's alleged infringement of claim 7 of the process patent turns on the Court's construction of the phrase "substantially pure regioisomer" in claim 1, the independent claim on which claim 6 and, in turn, claim 7 depend. At issue is the question of the scope of "substantially pure" in regard to the regioisomer p-CPK (i.e., the para regioisomer of cyclopropylketone), an intermediate in the manufacturing process: how pure is "substantially pure?"
A. Tentative Claim Construction of "Substantially Pure Regioisomer" in the Process Patent
At the preliminary injunction stage, the district court has the discretion to base its resolution on a tentative claim construction. Guttman, Inc. v. Kopykake Enters., 302 F.3d 1352, 1361 (Fed. Cir. 2002). "District courts may engage in a rolling claim construction, in which the court revisits and alters its interpretation of the claim terms as its understanding of the technology evolves." Id.
The Court decides claim construction as a matter of law: "the construction of a patent, including terms of art within its claim, is exclusively within the province of the court." Markman v. Westview Instruments, 517 U.S. 370, 372 (1996). "To ascertain the meaning of claims, we consider three sources: the claims, the specification, and the prosecution history." Markman v. Westview Instruments, 52 F.3d 967, 979 (Fed. Cir. 1995), aff'd, 517 U.S. 370 (1996) (citations omitted).
1. Ascertaining the Meaning Based on the Claims
The Court first looks to the language of the claims themselves to ascertain the meaning and scope of the phrase "substantially pure regioisomer." Claim 1 recites "a process of preparing a piperidine derivative compound" of a formula which includes both fexofenadine and fexofenadone, "said process comprising: providing a substantially pure regioisomer" p-CPK and "converting the substantially pure regioisomer to the piperidine derivative compound" using the compound azacyclonol ("AZA"). '703 Patent col.23 l.45 - col.24 l.34. Claim 6 adds onto this process a step in which the piperidine derivative compound is transformed into an end product in the fexofenadine family. Id. col.25 l.63 - col.26 l.16. Claim 7 recites the process of claim 6, with the end product being fexofenadine. Id. col.26 ll.17-32. Thus, in claim 7, the patented process begins with the "substantially pure regioisomer" p-CPK, often referred to as an intermediate, and finishes with the end product fexofenadine. The parties agree that there is nothing express or implicit in the words of claims 1, 6, or 7 that delimits the purity of the p-CPK intermediate that the process begins with. They agree as well that "substantially pure" has no ordinary or customary meaning to one of ordinary skill in the art. (Def.'s Opp. Br. 44.)
Claim 2 provides information relevant to construction of the phrase at issue. Nonasserted dependent claims may be helpful in construing a term in an independent claim, because the claims must be interpreted consistently. See Wright Med. Tech., Inc. v. Osteonics Corp., 122 F.3d 1440, 1445 (Fed. Cir. 1997) ("[W]e must not interpret an independent claim in a way that is inconsistent with a claim which depends from it"); accord Medrad, Inc. v. MRI Devices Corp., 401 F.3d 1313, 1317 (Fed. Cir. 2005).
Claim 2 depends from claim 1 and recites steps comprising the "providing a substantially pure regioisomer" of the previous claim. Id. col.24 l.35 - col.25 l.22. These steps comprise, in brief, producing a first mixture of regioisomers, which is hydrolyzed to form a second mixture of regioisomers, and then "recovering from the second mixture of regioisomers the substantially pure regioisomer" p-CPK. Id. col.25 ll.12-13. The parties do not dispute that "mixture" in claim 2 refers to a mixture of meta regioisomers and para regioisomers. The claim language thus establishes that a "substantially pure regioisomer" is something that is recovered from, and therefore, not the same as, a "mixture of regioisomers." This must mean that a "substantially pure regioisomer" is not a "mixture" of regioisomers. This supports an initial construction of "substantially pure regioisomer" as meaning "the regioisomer substantially different from a mixture." Moreover, if the mixture consists only of para and meta regioisomers, and a non-mixture is recovered, then this non-mixture must logically substantially consist of only the para regioisomer or the meta regioisomer.*fn1 Because the parties agree that, as a general rule, the meta regioisomers of fexofenadine are unwanted impurities that should be eliminated, and they do not dispute that one of ordinary skill in the art would have understood this at the time of application, it is reasonable to infer that "substantially pure regioisomer" in claim 2 means "the para regioisomer substantially not mixed with meta regioisomer." Because claims must be interpreted consistently, this analysis provides the initial construction of "substantially pure regioisomer," as used in claim 1.
Drawings in a patent may be a source of information in claim construction. Ferguson Beauregard/Logic Controls v. Mega Sys., LLC, 350 F.3d 1327, 1338 (Fed. Cir. 2003); Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1324 (Fed. Cir. 2002). In the chemical drawings used in the claims, benzene rings are drawn as hexagons with a circle inside. Each circle is labeled with a letter that corresponds to the substituent of the ring. Defendants observed, and Plaintiffs did not dispute, that the diagrams themselves indicate whether a chemical is or is not a mixture: the drawings of chemicals identified as mixtures in the claims all show a bond line connecting the hexagon to the circle, whereas the drawings of chemicals identified as substantially pure have no such connecting bond line.
This aspect to the drawings appears meaningful in examining claim 2. Thus, in claim 2, a diagram with a connecting line depicts "a first mixture of regioisomers" and "a second mixture of regioisomers." '703 Patent, col.24 l.58 - col.25 l.9. After stating the step of "recovering from the second mixture of regioisomers the substantially pure regioisomer," claim 2 shows a diagram without a connecting line. Id. col.25 ll.11-22. This provides additional support for the inference that the "substantially pure regioisomer" of claim 2 is not a "mixture."
In addition, the diagram for the piperidine derivative of claim 7, depicting the end product fexofenadine, has no connecting line. Id. col.26 ll.17-32. This supports the inference that the end product is also not a mixture. While this does not establish that the substantially pure intermediate and the end product have the same purity level, here is a place that the inventor could have expressly differentiated the purity of the substantially pure intermediate from the purity of the end product, but chose not to do so.
Because the inventor may be his own lexicographer, however, one cannot know from the claims alone exactly where to draw the line that distinguishes, in terms of purity level, between the "substantially pure regioisomer" and the "mixture."
2. Ascertaining the Meaning Based on the Specification
The Court next looks to the patent specification as a source of information for claim construction. Federal Circuit law is clear that courts must exercise great care when using the patent specification to limit the scope of claims:
[T]his court recognizes that it must interpret the claims in light of the specification, yet avoid impermissibly importing limitations from the specification. That balance turns on how the specification characterizes the claimed invention. In this respect, this court looks to whether the specification refers to a limitation only as a part of less than all possible embodiments or whether the specification read as a whole suggests that the very character of the invention requires the limitation be a part of every embodiment. For example, it is impermissible to read the one and only disclosed embodiment into a claim without other indicia that the patentee so intended to limit the invention. On the other hand, where the specification makes clear at various points that the claimed invention is narrower than the claim language might imply, it is entirely permissible and proper to limit the claims.
Alloc, Inc. v. Int'l Trade Comm., 342 F.3d 1361, 1370 (Fed. Cir. 2003) (citations omitted). The test for limiting claim scope from the specification is a stringent one: "the claims of the patent will not be read restrictively unless the patentee has demonstrated a clear intention to limit the claim scope using 'words or expressions of manifest exclusion or restriction.'" Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 906 (Fed. Cir. 2004) (quoting Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1327 (Fed. Cir. 2002)).
Of particular interest to the parties are the last two paragraphs in the "Background of the Invention" section:
The above second mixture of regioisomers can be converted to a third mixture of regioisomers of formula: [diagram of fexofenadine] Although the second mixture of regioisomers and the third mixture of regioisomers can be analyzed by HPLC experiments, a practical separation to obtain gram quantities of substantially pure regioisomers has not been achieved.
Each mixture (including the first), would be expected to contain 33% of the para isomer and 67% of the meta isomer. Since these components are inseparable, it has not been possible to obtain either of the regioisomers in each mixture in substantially pure form.
'703 Patent col.3 l.66 - col.4 l.24.
Plaintiffs argue that the only clear disavowal of claim scope in the specification appears in the second paragraph above: because it states that a mixture is not in substantially pure form, and also that a mixture may contain one of the regioisomers at a level of 67%, a "substantially pure regioisomer" must contain one of the regioisomers at a level greater than 67%. This, Plaintiffs argue, draws the line between "substantially pure" and "mixture" that one cannot discern from the claims themselves. Defendants argue that the analysis of the specification need not stop here, and this argument has merit.
The parties do not dispute that this quoted section refers to the prior art Carr process, that the first mixture refers to the intermediate straight-chain PK, the "second mixture of regioisomers" refers to fexofenadone, and the "third mixture of regioisomers" refers to fexofenadine. The second paragraph states that, because the para isomer and meta isomer of fexofenadone or fexofenadine cannot be separated, it has not been possible to obtain these regioisomers in substantially pure form. This establishes that 1) "substantially pure regioisomers" is a term that the inventor applied not only to p-CPK, as in claim 1, but also to fexofenadone and fexofenadine;*fn2 and 2) that "regioisomers in substantially pure form" are not mixtures, but are either the para or the meta isomer only, formed by separating mixtures. This second inference confirms the initial construction derived from the claims discussed supra.
The parties dispute how the cited paragraphs in the specification should be construed to limit the claims. Defendants argue that they establish that the para and meta regioisomers of fexofenadone and fexofenadine are inseparable. Because mixtures of these products are inseparable, Defendants argue, any separation needed to purify the end product must occur at an early stage, prior to the reaction producing fexofenadone. This issue will be discussed in detail infra.
Other parts of the specification provide information relevant to the construction of "substantially pure regioisomer."
i. Both the End Product and the p-CPK Intermediate are Described in the Specification as "Substantially Pure."
Although "substantially pure" describes only intermediates in the claims, it describes the end product at a number of points in the specification: in the abstract ("The present invention relates to a process for preparation of substantially pure piperidine derivative compounds" followed by generic formulae for fexofenadone and fexofenadine), '703 Patent at , in the summary of the invention ("The present invention relates to substantially pure piperidine derivative compounds" followed by the same formulae), Id. col.4 ll.27-28, in the detailed description of the invention (repeating the statement just quoted in the summary), Id. col 6 ll.19-20, and in two examples of processes for converting the substantially pure regioisomer to the substantially pure piperidine derivative, Id. col.16 ll.31 - col.19 l.35. In the background of the invention, in one sentence, the patent groups together intermediates and end products as "substantially pure." Id. col.4 ll.18-19.
Thus, the inventor describes the invention as involving substantially pure piperidine derivative compounds at three key, prominent points in the specification. While there are two additional points where this phrasing is used in the context of preferred embodiments, the first sentences of the abstract, summary, and detailed description do not refer to particular embodiments but to the invention as a whole. This clearly establishes a limitation of the invention to processes producing substantially pure piperidine derivative compounds. As will be seen infra, this conclusion is well-supported by the prosecution history. Moreover, the inventor does not in any way differentiate the meaning of "substantially pure" as it describes the end product from the meaning of "substantially pure" as it describes the intermediate.
ii. Both the End Product and the p-CPK Intermediate are Described in the Specification as "Regioisomers."
Although only intermediates are described as "regioisomers" in the claims, the specification refers to fexofenadone and fexofenadine regioisomers. In the background of the invention, regarding prior art mixtures of fexofenadine and fexofenadone, the patent states: "a practical separation to obtain gram quantities of substantially pure regioisomers has not been achieved." Id. col.4 ll.18-19. The patent then teaches that each mixture contains both meta isomer and para isomer, and that "[s]ince these components are inseparable, it has not been possible to obtain either of the regioisomers in each mixture in substantially pure form." Id. col.4 ll.22-24. This expands the scope of "regioisomers" to include not only the intermediate p-CPK, as mentioned in the claims, but also fexofenadone and fexofenadine.
The import of this reading of the specification is that, because both the end product and the p-CPK intermediate are described in the specification as "substantially pure," and both the end product and the p-CPK intermediate are described in the specification as "regioisomers," the specification does not support two definitions of "substantially pure," one for the intermediate and one for the end product, nor can "regioisomer" be read to connote or distinguish purity.
iii. The Piperidine Derivative Compounds have Pharmaceutical Uses
"Statements that describe the invention as a whole, rather than statements that describe only preferred embodiments, are more likely to support a limiting definition of a claim term." C.R. Bard, Inc. v. U.S. Surgical Corp., 388 F.3d 858, 864 (Fed. Cir. 2004).
The specification describes pharmaceutical uses of the substantially pure piperidine derivative compounds. The summary of the invention states: "These compounds are useful in pharmaceutical compositions, particularly as antihistamines, antiallergy agents, and bronchodilators." '703 Patent col.5 ll.6-8. The detailed description of the invention describes pharmaceutical uses of the end products at some length, beginning by stating: "The piperidine derivative compounds of the present invention can be utilized as the biologically active components in pharmaceutical compositions." Id. col.11 ll.34-36. The parties do not dispute that only the para regioisomer piperidine derivative compounds are biologically active; the meta regioisomer end product is not. Because only para regioisomer piperidine derivative compounds are biologically active, only these compounds can be utilized for the described use. This could suggest a limitation of the invention to a process producing para regioisomer piperidine derivative compounds. Yet this does not rise to the level of establishing a clear intention to limit claim scope through "words of manifest exclusion or restriction."*fn3
The detailed description teaches how to use the "compounds of the present invention" to "treat" humans. Id. col.12 l.27. It discloses treatment methods using the compounds and makes no mention of further purification before such methods as intravenous administration. Id. col.11 l.44.
While these statements appear to describe the invention as a whole, rather than preferred embodiments, again, one cannot characterize them as establishing a clear intention to limit claim scope through words of manifest exclusion or restriction. One is not led to the "inescapable conclusion," based only on these specification statements, that the end product of every embodiment must be ready for pharmaceutical use or must be at a particular level of purity. See Microsoft Corp. v. Multi-Tech Sys., 357 F.3d 1340, 1348 (Fed. Cir. 2004) (employing the "inescapable conclusion" standard in determining whether to find claim limitations in the specification).
Moreover, Plaintiffs argue that, while it would be incorrect to limit the patent to processes producing end products pure enough for pharmaceutical use, such a limitation would not defeat their argument that Ranbaxy has infringed. If this Court construed "substantially pure regioisomer" as to the intermediate to mean "purity sufficient to obtain a pharmaceutical grade piperidine derivative compound," Plaintiffs argue, Ranbaxy would literally infringe, since it necessarily uses p-CPK intermediate at a purity level sufficient to obtain a pharmaceutical grade piperidine derivative compound. Thus, even if this Court found a manifest restriction in the specification to processes producing end product pure enough for pharmaceutical use, this would not shield Ranbaxy from a finding of infringement.
iv. The Specification Does not Support two Standards of Substantial Purity
The language of the specification does not support two definitions of "substantially pure," one for the intermediate and one for the end product. The inventor applies the phrases "substantially pure" and "substantially pure regioisomers" indiscriminately to intermediate and to end product; there is no evidence that he intended anything other than one common definition. The specification does not, however, establish a clear scope for "substantially pure." Viewed as a whole, the language within the patent strongly suggests that "substantially pure" is a very high level of purity. While it is clear from the patent that a line separates what is "substantially pure" from what is a mixture, neither the claims nor the specification place that line with more clarity or certainty than the 67% line Plaintiffs point to. Because the inventor may act as his own lexicographer, he may define "mixture" and "substantially pure" in idiosyncratic ways. As such, the language of the patent, without more, does not justify limiting "substantially pure" beyond the 67% level Plaintiffs advocate; the language suggesting higher purity does not meet the standard of explicit restriction that the Federal Circuit requires in order to limit claim scope.
Plaintiffs argue that one of ordinary skill in the art would understand that purity standards for intermediates are "often different" from purity standards for end products. (Pls.' Reply Br. 101.) This statement, however, works against them. If one of ordinary skill in the art would understand that such purity standards are often different, one would sometimes understand that they are the same. This supports the conclusion from the specification that this is one of those times, and that "substantially pure" has one uniform meaning in the patent as a whole.
Plaintiffs state that there is nothing in the patent that expressly states that the purity standards are the same. (Id. at 101 n.38.) But, for this to get them to their conclusion, Plaintiffs require a default rule that makes no sense: the reader of the patent should assume that one phrase has different meanings in different contexts unless told otherwise. In reality, the default rule is opposite: the reader assumes that one phrase has a uniform meaning unless told otherwise. As such, in the absence of any express differentiation of the two standards in the patent or prosecution history, Plaintiffs have in effect admitted that one of ordinary skill in the art might understand that the "substantially pure" purity standard for the regioisomer intermediate is the same as that for the "substantially pure" regioisomer end product.
Further support for this interpretation comes from the deposition of the inventor, D'Ambra. Questioned specifically about this issue -- whether "substantially pure" means one thing as applied to the end product and another thing as applied to the intermediate -- D'Ambra admitted that this distinction does not appear in the patent: "Q: And where do I find that understanding in your patent? A: I don't believe it's clarified in there." (James Decl. Ex. ...