The Future of Prenatal Molecular Diagnostics: Impact of the Changing Patent Landscape

Abstract

*Fox Rothschild LLP, 2000 Market Street 20th Floor, Philadelphia, PA 19103-3222, USA E-mail: TRachinsky@foxrothschild.com Recent developments in US patent law will provide both challenges and opportunities for creating effective intellectual property and commercialization strategies for prenatal molecular diagnostic methods and may ultimately influence provider and patient access to certain tests. In Mayo v. Prometheus [1], the US Supreme Court addressed the legal standards for patent-eligible subject matter under 35 USC §101, with important implications for patents directed to diagnostic methods. In general terms, the patents-in-suit [101,102] claimed methods of optimizing the therapeutic efficacy for treatment of an immune-mediated gastrointestinal disorder by: administering a drug to a subject; and determining levels of drug metabolite(s), wherein the assayed metabolite levels are compared with predetermined levels to determine whether there is a need to increase or decrease the amount of drug administered. Under US patent law, certain subject matter is not eligible for patenting. Such patent-ineligible subject matter includes laws of nature, natural phenomena and abstract ideas. According to the Court, the relationship between the concentration of metabolites in the blood and the likelihood that a drug dosage would be effective constitutes a patent-ineligible ‘law of nature’. The Court then looked to see whether the claims additionally included an “inventive concept”, particularly one that is not a “well-understood, routine, conventional activity”, which would transform “unpatentable natural laws into patent-eligible applications of those laws”. Finding none, the Court held that the claims of the patents ‘effectively claim the underlying laws of nature themselves’ and are thus invalid. In its decision in AMP v. Myriad [2], the Supreme Court addressed the issue of patent-eligible subject matter for composition of matter claims directed to isolated nucleic acid molecules. Reversing years of US patent policy, the Court held that isolated (genomic) DNA segments are not patent-eligible, finding them to be products of nature. In contrast, cDNA were held to be patent-eligible subject matter, since such molecules are not naturally occurring. While the Myriad Supreme Court did not address diagnostic method claims, its decision impacts the validity of claims directed to isolated DNA molecules used in diagnosis. What may be of even greater concern is that, in view of the Court’s efforts to delineate what constitutes a ‘product of nature’ in the biotechnology context, its decision in Myriad may call into question the patentability of other isolated