More Diagnostic Patent Claims Fall—Despite following USPTO Guidelines
| May 3, 2019
Cleveland Clinic v. True Health Diagnostics
April 1, 2019
Lourie, Moore and Wallach. Opinion by Lourie. (non-precedential)
Summary
In a non-precedential opinion, the CAFC considered diagnostic patent claims ineligible. The CAFC dismissed recitation of detection of a biomarker using conventional tools as an “overly superficial” rephrasing of claims that were previously considered ineligible. The CAFC also indicated that it is not bound by USPTO guidelines, and implied that the relied-upon USPTO Example is inconsistent with Ariosa.
Details
This case relates to a diagnostic to detect heart disease. Myeloperoxidase (MPO) is an early marker of heart disease associated with atherosclerotic plaques. It was known in the prior art that MPO can be detected in surgically removed plaques, but it was not known that MPO is present in elevated levels in the blood of patients having atherosclerotic cardiovascular disease. The inventors disclosed a method of detecting MPO by lab techniques such as colorimetric-based assay, flow cytometry, ELISA etc, and then correlating the detected MPO to heart disease. Notably, the specification states that MPO can be detected “by standard methods in the art,” and that commercially available kits can be modified to detect MPO.
In Cleveland Clinic I, the CAFC held that method claims reciting “a method of assessing risk of having atherosclerotic heart disease” were invalid as reciting a law of nature without anything significantly more. See Cleveland Clinic v. True Health Diagnostics LLC, 859 F.3d 1352 (Fed. Cir. 2017), cert. denied, 138 S. Ct. 2621, (2018). In that case, the claims only recited a step of “comparing” MPO levels of a subject with MPO levels in a known non-diseased person.
However, this case presents slightly different claims based on same technology. Rather than reciting diagnosis or treatment, the present claims recite methods of detecting and identifying elevated MPO, with more detail. Specifically, the relevant claims are as follows:
Patent 9,575,065:
1. A method of detecting elevated MPO mass in a patient sample comprising:
a) obtaining a plasma sample from a human patient having atherosclerotic cardiovascular disease (CVD); and
b) detecting elevated MPO mass in said plasma sample, as compared to a control MPO mass level from the general population or apparently healthy subjects, by contacting said plasma sample with anti-MPO antibodies and detecting binding between MPO in said plasma sample and said anti-MPO antibodies.
Patent 9,581,597:
1. A method for identifying an elevated myeloperoxidase (MPO) concentration in a plasma sample from a human subject with atherosclerotic cardiovascular disease comprising: a) contacting a sample with an anti-MPO antibody, wherein said sample is a plasma sample from a human subject having atherosclerotic cardiovascular disease;
b) spectrophotometrically detecting MPO levels in said plasma sample;
c) comparing said MPO levels in said plasma sample to a standard curve generated with known amounts of MPO to determine the MPO concentration in said sample; and
d) comparing said MPO concentration in said plasma sample from said human subject to a control MPO concentration from apparently healthy human subjects, and identifying said MPO concentration in said plasma sample from said human subject as being elevated compared to said control MPO concentration.
2. The method of claim 1, further comprising, prior to step a), centrifuging an anti-coagulated blood sample from said human subject to generate said plasma sample.
Prosecution
In prosecution of these patents, the Applicant argued by analogy to Example 29 of the May 2016 USPTO eligibility guidelines. Example 29 presents two claims:
1. A method of detecting JUL-1 in a patient, said method comprising:
a. obtaining a plasma sample from a human patient; and
b. detecting whether JUL-1 is present in the plasma sample by contacting the plasma sample with an anti-JUL-1 antibody and detecting binding between JUL-1 and the antibody.
2. A method of diagnosing 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 by contacting the plasma sample with an anti-JUL-1 antibody and detecting binding between JUL-1 and the antibody; and
c. diagnosing the patient with julitis when the presence of JUL-1 in the plasma sample is detected.
According to the 2016 guidelines, claim 1 is eligible, because it does not recite a law of nature (pass on step 2A). However, in the USPTO’s view, claim 2 is ineligible because it recites a law of nature without reciting something significantly more (fail on steps 2A and 2B).
In prosecution, the Applicant argued that the “detecting” claim of the ‘065 patent is more similar to the “detecting” claim 1 of Example 29 (eligible) than it is to the “diagnosing” claim 2 of Example 29 (ineligible). The Examiner agreed and allowed the application.
As to the ‘597 claims, the Applicant successfully argued in prosecution that the “identifying” claim recites significantly more than a judicial exception, also relying on Example 29. The Applicant argued that it was not known to identify elevated MPO in plasma of patients having atherosclerotic cardiovascular diseases, even though it was previously known to detect MPO in plaques. The Examiner agreed and allowed the application.
District Court
The district court interpreted the claims as being directed to a law of nature, based on the recitations of “detecting elevated MPO mass in a patient sample…”, “….from a human having atherosclerotic cardiovascular disease”, and “identifying an elevated [MPO] concentration in a plasma sample from a human subject with atherosclerotic cardiovascular disease.” The district court concluded that the method is only useful for detecting elevated MPO associated with cardiovascular disease. In other words, the method is only useful for detecting a natural phenomenon.
As such, the district court concluded that the claims do not recite a general laboratory technique and instead are trying to “recast [a] diagnostic patent as a laboratory method patent.” The district court concluded that the claims are directed to detecting the correlation between MPO and the disease, rather than to detecting MPO more generally. Thus, the claims fail step 2A. Further, the additional steps are all well-known and conventional and thus fail step 2B. Specifically, the district court stated that “[i]f merely using existing, conventional methods to observe a newly discovered natural phenomenon were enough to qualify for protection under §101, the natural law exception would be eviscerated.”
CAFC
The CAFC agreed in holding that the claims are ineligible. Cleveland Clinic argued first that the claims are not directed to a natural law, but rather to a technique of using an immunoassay to measure MPO. However, the CAFC considered this distinction to be “overly superficial,” and stated that the claims are directed to a natural law (correlation between MPO and the disease). The CAFC characterized the difference between the claims at issue and the claims of Cleveland Clinic I as a “rephrasing” that does not make the claims less directed to a law of nature.
Cleveland Clinic also argued that the correlation is not a natural law because it can only be detected using certain techniques. However, the CAFC saw through this, and stated that the same is true for many of the natural laws at issue in previous cases. Specifically, the CAFC stated that “[i]nadequate measures of detection do not render a natural law any less natural.”
The CAFC also held that the claims do not recite an additional inventive concept. Cleveland Clinic argued that using a known technique in a standard way to observe a natural law confers an inventive concept. However, the CAFC stated that this reasoning has been dismissed is previous cases such as Athena Diagnostics v. Mayo and Ariosa v. Sequenom. Further to this point, the CAFC stressed that the MPO is detected using known techniques without significant adjustments.
Finally, the CAFC addressed the USPTO guidelines. Cleveland Clinic stated that the district court erred by not giving appropriate deference to Example 29 noted above. The CAFC agreed with True Health in stating the USPTO guidelines are neither persuasive nor relevant to the claims at issue, because the district court reached the correct decision.
The CAFC did not include an extensive discussion of the USPTO guidelines, but stated as follows:
While we greatly respect the PTO’s expertise on all matters relating to patentability, including patent eligibility, we are not bound by its guidance. And, especially regarding the issue of patent eligibility and the efforts of the courts to determine the distinction between claims directed to natural laws and those directed to patent-eligible applications of those laws, we are mindful of the need for consistent application of our case law.
Further with regard to Example 29, the CAFC stated that its claim 1 is “strikingly similar” to ineligible claim 1 of Ariosa. As such, the CAFC stated that although they have considered Example 29 and related arguments, Ariosa must control. Thus, the CAFC did not follow the USPTO’s guidelines.
Takeaway
- Patent eligibility of diagnostic methods continues to be highly problematic. However, Chris Coons (D-DE) and Thom Tillis (R-NC) have recently been holding meetings on the issue, and released a “framework” on April 17, 2019:
However, in view of competing interests of the life sciences industry and the software industry, as well as reluctance to change a long-standing law, legislative change may be farther away than one might hope.
- One relies on USPTO guidelines at their own risk. Here, less than 3 years after publication, a CAFC panel has declined to follow the USPTO’s guidelines. Since such guidelines do not have the force of law, the courts are not required to follow them. In fact, in this case, the CAFC was somewhat dismissive of the USPTO’s efforts regarding §101. It is quite possible that the much-lauded USPTO guidelines issued on January 4, 2019 might suffer the same fate.
- If trying to claim a diagnostic as a detection method, it is probably better to omit recitation of a specific disease and a high/low comparison in the claims. In the rare case it is possible, it would be ideal to disclose a non-diagnostic use of the detected compound in the specification.
