This month, the U.S. Court of Appeals for the Federal Circuit has handed down a pair of opinions concerning Section 101 in the field of pharmaceuticals and life sciences. In both cases, the district courts held claims of the patents at issue invalid for lack of patentable subject matter, and in both cases, the federal circuit reversed, finding the claims to be patent eligible.

The first case, Boehringer Ingelheim Pharmaceuticals Inc. et al. v. Mylan Pharmaceuticals Inc. et al., No. 2019-1172 (Fed. Cir. March 16, 2020), on appeal from the U.S. District Court for the District of New Jersey, concerned a patent claiming methods of treating metabolic diseases such as diabetes in a specific subset of patients for whom metformin, the traditional and widely used treatment for these diseases, is contraindicated by administering a DPP-IV inhibitor. The district court granted judgment on the pleadings under Rule 12(c) that the asserted claims were directed to ineligible subject matter under 35 U.S.C. § 101, under the two-step framework of Alice Corp. v. CLS Bank Int'l, 573 U.S. 208, 217 (2014).

The federal circuit reversed, finding that while the invention related to the discovery that DPP-IV inhibitors are substantially or mainly excreted via the liver, the claimed methods are directed to the treatment of a specific disease, for specific patients, using a specific compound at specific doses to achieve a specific outcome and therefore were patent eligible consistent with Vanda Pharmaceuticals, Inc. v. West-Ward Pharmaceuticals International Ltd., 887 F.3d 1117 (Fed. Cir. 2018). The court specifically noted that although certain DPP-IV inhibitors are metabolized by the liver rather than the kidney, the claims were not drawn to that natural ability.

Although this was a straightforward application of the Vanda precedent, the federal circuit also issued a much more detailed opinion in Illumina Inc. et al. v. Ariosa Diagnostics Inc. et al., No. 2019-1419 (Fed. Cir. March 17, 2020), which concerned claims directed to a method of preparing a fraction of cell-free DNA that is enriched in fetal DNA. This method was based on the underlying discovery that the small amount of circulatory extracellular fetal DNA has a relatively small size of 500 base pairs or less, while the majority of circulatory extracellular maternal DNA has a size of greater than 500 base pairs. For context, a prior but unrelated patent, which claimed a method for detecting such cell-free circulatory fetal DNA, had been held as invalid under 35 U.S.C. § 101 because its claims were directed to the natural phenomenon that cell-free fetal DNA exists in maternal blood.

The trial court in the U.S. District Court for the Northern District of California held that the claims at issue for these later patents were likewise directed to patent ineligible subject matter and were therefore invalid. The federal circuit again reversed, stating that this was not a diagnostic or method of treatment case but a method of preparation case. The court identified the natural phenomena underlying the claims as cell-free fetal DNA, which tends to be shorter than cell-free maternal DNA in a mother's bloodstream, and determined that the claims were not directed to that phenomenon but rather to a patent-eligible method that utilizes it.

The court specifically determined that the claimed methods include specific process steps of selectively removing larger DNA fragments to change the composition of the mixture from the naturally occurring ratio in the mother's blood and that doing so achieves more than simply observing that fetal DNA is shorter than maternal DNA or detecting the presence of that phenomenon. The court used this basis to distinguish the instant claims from the invalid ones previously considered in the Mayo, Athena and Cleveland Clinic decisions, which were all directed to simply detect a natural phenomenon. The court ultimately held that while the claimed methods utilize the natural phenomenon discovered by the inventors, they employed a physical process step to selectively remove fragments of cell-free fetal DNA and were therefore patent eligible under step one of the Alice/Mayo test, so step two of the test need not be considered.

Judge Jimmie Reyna issued a dissent, concluding that the claims are directed to the natural phenomenon that extracellular fetal DNA tends to be shorter than extracellular maternal DNA. Reyna criticized the majority for creating a new "method of preparation" category rather than properly considering the claims as diagnostic methods and using that unique category to avoid the precedent of Mayo, Athena, Cleveland Clinic and other decisions finding such claims patent ineligible. Judge Reyna concluded that the claims at issue were directed to the natural phenomenon based on multiple statements in the specification, including that the discovery of the DNA size relationship was a "surprising finding" and "forms the basis of the present invention," as well as the fact that the claimed method begins and ends with a naturally occurring substance, the extracellular DNA strands, and that isolating or partitioning a certain fraction of that DNA does not change it. Judge Reyna also criticized the majority for ignoring the "claimed advance" inquiry; the claimed advance is not an improvement to underlying DNA-processing technology but simply the selection of base pairs to be detected using commercially available DNA-processing technology and, unlike in CellzDirect, does not create any new laboratory techniques. Judge Reyna further concludes that a process that merely changes the composition of a naturally occurring substance without altering the naturally occurring substance itself is not patent eligible.

Finding that the claims are directed to a natural phenomenon, Judge Reyna applied step two of the Alice/Mayo test, finding that the claimed methods are not additional new and useful features, because the methods are not new and do not claim any new and useful improvements to DNA separation techniques. The fact that such techniques had never before been applied to the newly discovered natural phenomenon does not render them new and useful.

Finally, Judge Reyna invoked the doctrine of preemption, finding that the claims tied up future innovation premised on the underlying natural phenomenon, because no skilled artisan would be able to rely on the natural phenomenon to isolate cell-free DNA.

Judge Reyna's dissent concluded that the court should have found the claims at issue invalid as claiming ineligible subject matter, because they were directed to a natural phenomenon (the size of fetal versus maternal extra cellular DNA), failed to add any new and useful feature to the field of DNA separation techniques and would preempt the field the cell-free DNA isolation.

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