Recent Development on Patent Eligibility of Method of Treatment Claims

The United States Patent and Trademark Office (USPTO) recently published a new revision to the Ninth Edition of the Manual of Patent Examining Procedure (MPEP) (Revision 08.2017). This revision added a number of chapters about patent-eligibility, the duty to disclose information to the office and other key patent law issues. For patent practitioner in life sciences, one of the notable changes in this revision includes a new section 2106.04 (b), which provides guidance regarding subject matter eligibility, including method of treatment claims.

In Section 2106.04(b) of the MPEP, the USPTO states that “not every claim describing a natural ability or quality of a product, or describing a natural process, is necessarily ‘directed to’ a law of nature or natural phenomenon,” for example, “a method of treating cancer with chemotherapy is not directed to the cancer cells’ inability to survive chemotherapy, and a method of treating headaches with aspirin is not directed to the human body’s natural response to aspirin,” citing the Federal Circuit’s opinion in Rapid Litig. Mgmt. v. CellzDirect, Inc. for support.[1] Not surprisingly, the Federal Circuit jurisprudence on subject matter eligibility of treatment claims, as recognized in the new MPEP section, is that a method of treatment claim is not categorically patent ineligible.

However, when a treatment claim also recites diagnostic steps that rely on a “natural correlation,” it is not clear whether the Federal Circuit would still consider this type of treatment claim patent eligible. The newly added MPEP sections do not address this type of treatment claim, but the USPTO’s guidelines issued on May 4, 2016 for subject matter eligibility in life sciences has provided some clue of the Patent Office’s stance on this issue.[2]

Example 29 of the guidelines relates to diagnosing and treating a fictitious disease called “julitis” based on the detection of a newly identified protein marker called JUL-1.[3] Example claim 6 recites:

6.  A method of diagnosing and treating julitis in a patient, said method comprising …

a. obtaining a plasma sample from a human patient;

b. detecting whether JUL-1 is present in the plasma sample;

c. diagnosing the patient with julitis when the presence of JUL-1 in the plasma sample is detected; and

d. administering an effective amount of anti-tumor necrosis factor (TNF) antibodies to the diagnosed patient.

Despite the fact that the JUL-1 protein is naturally correlated with julitis, that the anti-TNF antibodies are both a “nature-based product” and a “conventional” therapy for julitis, and that administering these antibodies to treat a patient diagnosed with julitis was known at the time of filing, the guidelines provide that the treatment claim is patent eligible because “the totality of these steps including the recitation of a particular treatment (administration of an effective amount of anti-TNF antibodies) in step d integrate the exception [the correlation of JUL‑1 to julitis] into the diagnostic and treatment process, and amount to more than merely diagnosing a patient with julitis and instructing a doctor to generically ‘treat it.’”[4]  The USPTO concludes that the administering step, when considered in combination with the other steps, is sufficient to transform the claim into a patent eligible matter.[5]    

However, several district court decisions have found treatment claims reciting diagnosing or patient selection and administering steps similar to the above example to be patent ineligible.[6]  One example is Mallinckrodt Hospital Prods. IP Ltd. v. Praxair Distrib., Inc.,[7] in which Judge Sleet invalidated method of treatment claims for being directed to laws of nature. The treatment claim at issue is reproduced below:

1. A method of treating patients who are candidates for inhaled nitric oxide treatment, which method reduces the risk that inhalation of nitric oxide gas will induce an increase in pulmonary capillary wedge pressure (PCWP) leading to pulmonary edema in neonatal patients with hypoxic respiratory failure, the method comprising:

(a) identifying a plurality of term or near-term neonatal patients who have hypoxic respiratory failure and are candidates for 20 ppm inhaled nitric oxide treatment;

(b) determining that a first patient of the plurality does not have left ventricular dysfunction;

(c) determining that a second patient of the plurality has left ventricular dysfunction, so is at particular risk of increased PCWP leading to pulmonary edema upon treatment with inhaled nitric oxide;

(d) administering 20 ppm inhaled nitric oxide treatment to the first patient; and

(e) excluding the second patient from treatment with inhaled nitric oxide, based on the determination that the second patient has left ventricular dysfunction, so is at particular risk of increased PCWP leading to pulmonary edema upon treatment with inhaled nitric oxide.

The district court conducted the two-step test under the Mayo/Alice analytical framework, and determined that because the treatment of hypoxic respiratory failure with inhaled NO (iNO) was known, “the core of the alleged invention” was a patent ineligible law of nature.[8]  The court reasoned that “that ‘invention’ is really a patient populations’ natural physiological response to 20 ppm of inhaled nitric oxide treatment. While man discovered the adverse physiological response that occurs when some patients receive iNO, such a discovery does not amount to innovation.”[9]  The court then stated: “the natural phenomenon is that some patients with preexisting LVD have a negative reaction to treatment. Plaintiffs cannot seriously contend that it is a new practice to exclude certain patients from treatment with a drug when those patients are at an increased risk of experiencing negative side effects from the drug.”[10] The district court did not consider the steps of administering iNO to certain patients, while excluding others from treatment, sufficient to transform the claim into patent eligible subject matter.[11]  This holding appears inconsistent with the Patent Office’s reasoning regarding claim 6 of the julitis example discussed above, where the integration of the natural correlation into a diagnostic and treatment process was sufficient to render the claim as a whole patent eligible.

Several other district court decisions, including Endo Pharmaceuticals Inc. v. Actavis Inc.[12], Boehringer Ingelheim Pharmaceuticals, Inc. v. HEC Pharm Co.,[13] and Vanda Pharamceuticals Inc. v. Roxane Lab., Inc,[14] also found treatment claims including a diagnostic or patient selection component patent ineligible. Several of these cases are now on appeal, and it will be interesting to see whether the Federal Circuit sides with the USPTO, or with the district courts.