Athena Diagnostics Sues Mayo in Case That Implicates Patent Eligibility Doctrine

On June 2, 2015, Athena Diagnostics sued Mayo Collaborative Services (the Mayo Clinic and its associated reference laboratory) in the District of Massachusetts for infringement of US patent number 7,267,820. On its face, the patent is assigned to two European entities, Isis Innovation Limited and Max-Planck, but Athena represents that it is the exclusive licensee of the patent.

The patent claims methods for detecting antibodies to a protein called muscle-specific tyrosine kinase (“MuSK”).  The method is useful as a diagnostic for certain rare forms of an autoimmune disorder, Myasthenia gravis, that is characterized by the presence of autoantibodies directed against the patient’s own MuSK. Athena offers quantitative testing for the presence of MuSK-associated autoantibodies.

According to the complaint, prior to May 19, 2015, medical practitioners associated with Mayo utilized Athena for quantitative detection of MuSK-associated antibodies. However, Mayo has developed its own in-house tests for the autoantibodies, and as of May 19, 2015 it has directed its practitioners to use its in-house test instead of Athena’s. This is analogous to what happened in the case of Prometheus v. Mayo, where Mayo originally utilized the patent owner’s diagnostic test but then, presumably as a cost-saving measure, switched over to their own internal testing procedure.

Patent eligibility could become a significant issue in this case. Athena is clearly cognizant of this fact, emphasizing in this complaint that its patented methods “involve using man-made chemical reagents capable of detecting antibodies to an epitope of” MuSK. The illustrative independent claim in the patent recites:

1.       A method for diagnosing neurotransmission or developmental disorders related to muscle specific tyrosine kinase (MuSK) in a mammal comprising the step of detecting in a bodily fluid of said mammal autoantibodies to an epitope of muscle specific tyrosine kinase (MuSK).

The claim seems to implicate patent eligibility concerns, particularly in the event a court were to find that the presence of autoantibodies to MuSK in a patient’s body fluid is a natural phenomenon, and that the claim does not include sufficient additional inventive attributes to qualify for patent protection. The patent also includes a number of dependent claims that recites methods of performing the test with a greater degree of specificity, including the use of labeled antibodies. However, if the court follows the path set by Myriad II and Ariosa Diagnostics, it could very well conclude that these methods for detecting the autoantibodies are too conventional, and not sufficiently inventive, to render the claims patent eligible.

Of course, we are still waiting to hear what the Federal Circuit has to say about the district court's decision in Ariosa Diagnostics. But the present lawsuit between Athena and Mayo is one to keep an eye on for those interested in the patent eligibility of diagnostic methods.