Legal blow to Sequenom as global NIPT market expands

18 September 2014

Claims that a key US patent no. 6,258,540 held by Sequenom, the molecular diagnostic testing company that began the now the increasingly contested non-invasive prenatal testing (NIPT) commercial market, are invalid have been largely upheld.

The patent, which underpins Sequenom’s MaterniT21 Plus test, was invalidated last year by the District Court for the Northern District of California as a ruling against Sequenom, who had been seeking a summary judgement against rival company Ariosa for patent infringement. This decision, currently on appeal with the Court of Appeals for the Federal Circuit, stated that the patent was ineligible on the basis that it pertains to a naturally occurring phenomenon (the presence of cell-free fetal DNA in the maternal bloodstream) despite the fact that it claims a method of testing for paternally inherited nucleic acids of fetal origin and various applications.

Now in a final decision, the US Patent and Trademark Office (USPTO) board has ruled that, whilst certain claims in the original patent must be upheld, many others are ineligible and must be excluded. The claims excluded from the patent were ruled ineligible either on the basis that they represented unpatentable natural phenomena (the fetal DNA), or because they involved insufficiently inventive steps that would be obvious to any similarly skilled expert (the application of PCR-based methods to amplify the fetal DNA to levels great enough for detection).

Sequenom argued that the detection of fetal DNA via technological processes was in itself inventive since no-one before the inventor of the technique (Professor Dennis Lo, then of the University of Oxford) had considered attempting it. They also said that since there are other scientific methods of achieving the same ends without patent infringement, the patent claims were not pre-emptive, but the USPTO disagreed.

This decision is the latest blow for Sequenom and is anticipated to further weaken profitability; already, the company’s share values have fallen. Meanwhile, the triumphant Ariosa has announced introduction of a new microarray DNA quantification-based method for their own Harmony non-invasive test, said to offer faster turnaround times than the previous sequencing-based approach.

Other rival commercial test providers are likely to be heartening by the judgement, but legal disputes are nevertheless unlikely to dissipate. The global market for non-invasive prenatal diagnostics, last year estimated to have a value in approaching US$330 million, is expected to show rapid growth in the next few years into the billions, so there is plenty to play for in terms of intellectual property. Sequenom itself has already said it plans to bring a new and much cheaper form of NIPT to the market.

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