Palmetto v. AstraZeneca : The scope of intent as a claim element

Background

Palmetto Pharmaceuticals LLC (“Palmetto”) is the assignee of reexamined U.S. Patent No. 6,465,516 (“the ’516 Patent”), entitled “Method of Stimulating Nitric Oxide Synthase,” which relates to administering Hmg-CoA reductase inhibitors (also known as statins) to treat nonhyperlipidemic subjects who would benefit from increased nitric oxide production. Claim 1 of the ’516 Patent reads as follows (with the claim terms relevant to this article in bold):

1. A method for treating a nonhyperlipidemic subject who would benefit from increased Nitric Oxide production in a tissue comprising:

administering to the nonhyperlipidemic subject in need of such treatment a Hmg-CoA reductase inhibitor in an amount effective to increase Nitric Oxide production in said tissue of the subject.

Initial claim construction in Special Master’s report and recommendation

With the consent of the parties, the Court appointed a Special Master who issued a Claim Construction Report and Recommendation on 9 March 2015. See Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, D.I. 411, at 1 (D.S.C. 9 March 2015) (“Report”). One set of disputed claim terms—“a subject who would benefit from increased Nitric Oxide production” and “the subject in need of such treatment”—raised a dispute between the parties regarding the necessary mental state of the treating physician.

Both parties proposed constructions requiring some level of intent on the part of the treating physician. ¹ However, Palmetto argued that “the person practicing the method must intend to treat a subject who is at risk for cardiovascular disease conditions and adverse events,” while AstraZeneca argued that the treating medical professional must have “the intentional purpose of increasing nitric oxide production” in the tissue of a subject “having a recognized need for increased Nitric Oxide production” in such tissue. Report at 14. In other words, Palmetto argued that the treating physician must intend only to treat cardiovascular disease to infringe (regardless of the specific biochemical mechanism—such as increased nitric oxide production—used to treat that cardiovascular disease), while AstraZeneca argued that there was no infringement unless the doctor specifically intended to increase nitric oxide production as the biochemical mechanism used to treat the disease.

In arguing whether the intent should focus on the disease to be treated versus the biochemical mechanism, the parties sparred over the correct interpretation of Jansen v. Rexall Sundown Inc., 342 F.3d 1329 (Fed. Cir. 2003). Jansen involved U.S. Patent 4,945,083, Claim 1 of which reads as follows:

A method of treating or preventing macrocytic-megaloblastic anemia in humans which anemia is caused by either folic acid deficiency or by vitamin B₁₂ deficiency, which comprises administering a daily oral dosage of a vitamin preparation to a human in need thereof comprising at least about 0.5 mg of vitamin B₁₂ and at least about 0.5 mg of folic acid.

AstraZeneca argued that, given the “nearly identical” claim language, Jansen’s requirement of intentionality should also apply to the claim construction at issue here. Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, Def.’s Op. Markman Br., D.I. 367 at 22–23 (D.S.C. 21 July 2014).

Palmetto argued that Jansen’s holding was inapplicable, pointing to the fact that Jansen involved intent by laypersons purchasing an over-the-counter medication (rather than the prescription statins at issue in the present case) and to the Jansen patent’s “unique and lengthy prosecution history” leading to the court’s claim construction. Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, Pl.’s Op. Claim Constr. Br., D.I. 368 at 15–17 (D.S.C. 21 July 2014). In addition, Palmetto argued that the ’516 patent was not limited to the treatment of a single condition, but to the goal of treating any of a range of cardiovascular symptoms, through the means of increasing nitric oxide production in a tissue. See id.

The Special Master rejected the distinctions proffered by Palmetto, finding that the Jansen court required its method of treatment to be performed for the “intentional purposes as stated within the claim,” and held that the language in the ’516 Patent was “nearly parallel” with the language of the claims in Jansen. Report at 15. The Special Master therefore adopted a construction consistent with AstraZeneca’s proposed construction, construing “a subject in need of such treatment” to mean “a subject having a recognized need for Nitric Oxide production in a tissue” and requiring that the “method for treating a nonhyperlipidemic subject who would benefit from increased Nitric Oxide production in a tissue” be conducted with the intentional purpose of “increasing Nitric Oxide production in said tissue of the subject.” Id. at 16–17.

Adoption of report and stipulation of non-infringement in district court

Palmetto moved to modify the report, arguing that the Special Master had misapplied Jansen and therefore erred in his claim construction. According to Palmetto, the Special Master’s reading of Jansen would allow doctors to escape liability for infringement by creating a “perverse incentive” to remain ignorant of the biological mechanism behind the treatment of a particular disorder, and noted that the court in a related case had held the same. Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, D.I. 415, Plaintiff’s Mot. to Modify Claim Constr. Report at 2 (D.S.C. Apr. 6, 2015) (“Motion to Modify”), citing Charleston Medical Therapeutics, Inc. v. AstraZeneca LLP, Nos. 2:13-cv-2078-RMG & 3438-RMG. ² Further, Palmetto argued, this construction was inconsistent with the way that physicians actually practice medicine, which is more likely to involve deliberate analysis of how to treat a recognized condition rather than targeting a biochemical mechanism. See id. at 5–7.

To distinguish Jansen, Palmetto argued that Jansen involved a non-prescription vitamin supplement, where the alleged direct infringers were the customers who bought the vitamin as a form of treatment for anemia, rather than medical professionals prescribing a drug for such a purpose. See id. at 4-5. Palmetto, therefore, argued that the claim construction analysis in Jansen should not apply in this case involving physician prescribed drugs. See id. Instead, Palmetto argued that the judge’s construction in Charleston Medical Therapeutics was correct: the claim requires that the person practicing the method must intend to treat a disorder that happens to be mediated by nitric oxide, but need not realize that the disorder is in fact mediated by nitric oxide. See id. at 5–6. Finally, Palmetto argued that the Special Master’s construction (focusing on the intent to address a biochemical mechanism) contradicted certain dependent claims requiring the patient to be selected on the basis of having hypertension (rather than on the basis of a recognized need for increased nitric oxide production.) See id.at 8–9.

AstraZeneca defended the Special Master’s claim construction, arguing that he was correct to find close parallelism between the language of the claim in Jansen and the language of the ’516 Patent claim. Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, D.I. 418, Def.’s Resp. to Pl.’s Mot. to Modify Claim Constr. Report at 2–3 (D.S.C. 23 April 2015) (“Def.’s Resp.to Mot. to Modify”). AstraZeneca argued that, because the preamble of the ’516 Patent specifically states the purpose of the method—to increase nitric oxide production—Jansen requires an intent by the person performing the method to achieve the purpose in the preamble. See id. AstraZeneca also emphasized other language within the ’516 Patent’s specification focusing on the goal of increasing nitric oxide production, as well as statements during its reexamination history. See id. at 3–4, 6–8. Additionally, AstraZeneca disputed Palmetto’s attempt to distinguish between prescription and non-prescription drugs under Jansen, citing cases where previous courts had applied Jansen in the prescription drug context—Pfizer Inc. v. Teva Pharms. USA, Inc., 803 F. Supp. 2d 397, 408-09 (E.D. Va. 2011) (finding Jansen’s “purposiveness argument persuasive” in case involving Viagra® (sildenafil), a prescription medication); Wyeth v. Mylan Pharms., Inc., 2009 WL 1457732, at *10 (N.D. W. Va. 2009) (applying Jansen’s purpose requirement to claim construction in case involving Effexor® (venlafaxine), a prescription medication); and Schering Corp. v. Glenmark Pharm. Inc., USA, no. CIV A 07-1334 (JLL) 2008 WL 4307189 at *8–9 (D.N.J. 16 September 2008) (applying Jansen and finding intent requirement in claim construction involving Zetia® (ezetimibe), a prescription medication). See Def.’s Resp.to Mot. to Modify at 5–6. Relatedly, AstraZeneca argued, a physician is more likely than the average consumer to understand the biochemical basis behind a disease, which should support more specific intent requirements. See id. at 6. Finally, AstraZeneca distinguished the construction in CMT on the basis that the claim language focused on a particular category of disorder, rather than a subgroup of patients with a specific biochemical “need.” See id. at 9–11.

Based on the briefing by the parties and oral argument, the district court adopted the Special Master’s report in full, including the contested claim construction relating to intent. See Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, D.I. 442, Order Adopting Report (D.S.C. Nov. 30, 2015). Noting the parallels between the ’516 Patent’s language and the claim language in Jansen, the court found that the preamble requiring “treating a nonhyperlipidemic subject who would benefit from increased Nitric Oxide production” set forth the objective of the method, and therefore the intentional purpose for which the method must be performed. Id. at 8. The court was also persuaded by AstraZeneca’s argument that Jansen had been applied to prescription drugs by other courts, and noted that in Jansen, the prescription/non-prescription distinction had been analyzed in the context of infringement, not claim construction. Id. at 8–9. In addition, the court agreed with AstraZeneca that the intrinsic evidence relating to increasing nitric oxide production was more persuasive than Palmetto’s extrinsic evidence of common medical practice and understanding. Id. at 9. ³ Finally, the court approved of AstraZeneca’s distinction between the ’516 Patent, which specified the need to increase a particular chemical, and the patent at issue in CMT, which involved treating a particular disorder. See id. at 10–11.

Based on the district court’s claim construction decision, the parties entered a joint stipulation for entry of final judgment allowing the case to be promptly appealed. Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 2:11-807-SB, D.I. 443 (D.S.C. Dec. 8, 2015). In particular, the parties stipulated that, under the district court’s decision, Palmetto would not be able to prove direct infringement of the asserted claims of the ’516 Patent, presumably because of a lack of evidence regarding the specific intentions of prescribing physicians to increase nitric oxide production. See id.

Appeal and briefing at Federal Circuit

Palmetto appealed to the Federal Circuit, echoing its previous arguments on the intent requirement imposed by the district court as part of claim construction. See Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 16-1455, D.I. 25, Pl.’s Op. Br. (Fed. Cir. March 23, 2016) (“Pl. Op. Br.”). In addition, Palmetto emphasized that the intent requirement in Jansen was grounded in extensive prosecution history, and involved the condition to be treated rather than the biological mechanism of action. See id. at 17–18, 21–23, 26–29. Citing the general rule that intent is not an element of direct patent infringement, Palmetto suggested that courts should be particularly reluctant to adopt claim constructions that require proof of a defendant’s mental state, and that it was therefore particularly erroneous for the district court to import Jansen’s intent requirement into the current case. Id. at 24–26. Furthermore, because the ’516 Patent identifies the target subjects as those who would “benefit from increased Nitric Oxide production,” Palmetto argued that the method claims are tied to the desired benefit: treatment of a disease state, not direct alteration of nitric oxide levels. Id. at 30–34.

In response, AstraZeneca also its reiterated earlier arguments, further emphasizing that Palmetto’s desired construction could substantially broaden the patent to encompass all treatment of a disease state, regardless of the patient’s nitric oxide levels. See Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 16-1455, D.I. 32, Def.’s Op. and Resp. Br. at 3–5, 36–44 (Fed. Cir. May 19, 2016) (“Def. Resp. Br.”). AstraZeneca argued that existing case law clearly supports some intent requirement for method-of-treatment claims, and that Jansen’s identification of the “intentional purpose for which the method must be performed” supports the idea that the ’516 Patent’s stated goal of increasing nitric oxide production should be read as a claim limitation, particularly in light of the intrinsic evidence. ⁴ Id. at 28–36. AstraZeneca also disputed that Jansen’s holding relied heavily on prosecution history, arguing that it was “bolstered” rather than entirely inspired by prosecution history. Id. at 35.

Palmetto responded by arguing that its construction would not broaden the claim scope to include all treatment, regardless of connection to nitric oxide: rather, the diagnostic criteria for administering Crestor® necessarily select for patients who would benefit from increased nitric oxide production. See Palmetto Pharms. LLC v. AstraZeneca Pharms. LP, no. 16-1455, D.I. 36, Pl.’s Rep. at 2–5 (Fed. Cir. June 28, 2016). Palmetto also argued that, regardless of Jansen’s holding, other precedent cited in its opening brief supported the general principle of avoiding intent limitations in patent claim construction. See id. at 13–15; see also Pl. Op. Br. at 24 (listing cases on lack of mental state requirement for direct patent infringement).

Conclusion—Rule 36 affirmance and implications

On December 9, 2016, a Federal Circuit panel comprised of Judges Moore, Wallach, and Chen entered a Federal Circuit Rule 36 affirmance, summarily affirming the district court’s decision without issuing a written opinion. Without an opinion, it is of course difficult to determine the Federal Circuit’s precise rationale for upholding the district court’s claim construction. However, it appears that the Federal Circuit is willing to allow the scope of a method-of-treatment claim to be limited to the intentional targeting of a particular specified biochemical pathway, rather than the treatment of an associated disease—at least, in cases where the claim language resembles the language in Jansen and Palmetto. Future litigators asserting similar claims may want to consider whether they are able to offer state-of-mind evidence regarding accused direct infringers, or whether (as for Palmetto) an unfavorable claim construction ruling on prescriber intent will foreclose any possibility of building an infringement case. In addition, patent prosecutors for future method-of-treatment claims may wish to exercise additional caution in drafting claims predicated on following a specific biochemical pathway, rather than targeting treatment of a particular disease state: drafting claims targeted to both of these options may be the best way.