Vanda v. West-Ward Pharmaceuticals: Good News for the Patent Eligibility of Diagnostics and Personalized Medicine, with Some Important Caveats

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In Mayo v. Prometheus, decided in 2011, the U.S. Supreme Court invalidated patent claims directed towards diagnostic methods useful in the optimization of drug dosage for the needs of an individual patient, i.e., an example of personalized medicine, based on the Court’s determination that the claims were directed towards a patent ineligible law of nature. Notably, the claims in Mayo did not recite a step of applying the information generated by the test, e.g., a step of administering the drug to a patient at the optimized dosage. Some, including this author, have speculated that inclusion of such a step might have saved Prometheus’ claims. In 2018 the U.S. Court of Appeals of the Federal Circuit issued a decision in Vanda Pharmaceuticals v. West-Ward Pharmaceuticals International Limited wherein a divided panel held that inclusion of a step requiring action based on the result of a diagnostic test rendered the claims patent eligible. This is good news for innovators in diagnostics and personalized medicine, but there are some important caveats. While the Vanda majority makes a compelling argument that the claims at issue are patent eligible under Mayo, a well-reasoned dissent comes to the opposite conclusion. So it is not clear whether Vanda represents the last word on the subject, given that other judges on the Federal Circuit might agree with the dissent. Another important caveat is that the inclusion of an action step likely renders the claim difficult, if not impossible, to enforce, depending upon the nature of the alleged infringement. In Vanda, the court’s finding of infringement hinged upon the fact that the infringer, a generic drug company seeking FDA approval to market a generic version of the patent owner’s branded drug, was required by FDA law to include directions on the product label essentially advising doctors to perform the claimed method. Absent this fairly direct linkage between a mandated drug label and the claimed method, the issue of divided infringement will in many cases limit the enforce-ability of diagnostic method claims that recite an action step. In particular, if Prometheus had positively recited an action step in its claims the company would not have been able to establish infringement by a competing diagnostic testing company like Mayo.

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Biotechnology Law Report