The US Supreme Court has said that medical tests that rely on correlations between drug doses and treatment cannot be patented

The US Supreme Court has said that medical tests that rely on correlations between drug doses and treatment cannot be patented because they are based on laws of nature. In doing so it threw out Prometheus Laboratories’ lawsuit against Mayo Collaborative services. At issue were patents held by Prometheus on a process for analysing blood tests to measure the effects of different drug dosages to manage autoimmune gastrointestinal diseases such as Crohn’s.

The court ruled that an application of a law of nature is not always patentable. As a result, some patent attorneys are warning that this unanimous decision, reached on 20 March, could cripple the biotechnology and pharmaceutical industries. Patent attorneys say the ruling seems to overrule a long line of Supreme Court cases that say otherwise.

In its ruling, the US’s highest court reversed a judgment delivered by a lower court in 2009, which had affirmed that claims that cover methods of optimising the dosages of certain drugs for treating gastrointestinal disorders can be patented. Prometheus’ lawsuit was prompted by the Mayo Clinic’s development of a similar test to determine correct dosing of thiopurine drugs.

Harry Shubin, a former patent examiner for the US Patent and Trademark Office (PTO) and patent attorney for Millen, White, Zelano and Branigan in the US, says the decision has implications beyond the specific type of diagnostic claimed by Prometheus. Shubin, who has pharma clients, says it could affect not only the drug and biotech sectors, but also agriculture and hydrocarbon processing too.

The court decided that the steps that Prometheus, a subsidiary of Nestlé, had claimed to represent an ‘active’ human intervention were already well-established and routine. Therefore, patent attorneys warn that there will be great uncertainty across various industries about how to write a patentable claim.

The Mayo Clinic said it was pleased by the court’s decision. ‘The Mayo Clinic chose to pursue this lengthy litigation process because we believed it was in the best interests of our patients,’ said John Noseworthy, president and chief executive of the Mayo Clinic. ‘This decision concerns the value of delivering high quality patient care in a timely manner and at an affordable cost.’

Virginia patent attorney Gene Quinn agrees. ‘When courts focus on the patentability of subject matter and make rulings like this, they kill an entire line of research and innovation,’ he tells Chemistry World. ‘Without patents, people just aren’t going to pursue this - it’s so expensive and if you can’t have exclusive rights, why would you do it.’

Quinn estimates that tens of thousands of patents will now have no enforceable claims and potentially hundreds of billions of dollars in corporate value have been erased. He calls the decision a ‘disaster’, and says it represents a ‘cataclysmic change’ for patent law.

Unsurprisingly, the Biotechnology Industry Organization (BIO) is also sounding the alarm. The lobby group’s deputy general counsel for intellectual property, Hans Sauer, said he was ‘surprised and disappointed’ by the decision. He noted that BIO and others warned about the unintended consequences of attempting to use patent eligibility as a basis to strike down such patents for biomarker-based diagnostic methods.

According to Sauer, the court’s opinion doesn’t appropriately recognise the importance of personalised medicine and of the research and investment incentives needed to develop new individualised therapies for untreated diseases. He said BIO doesn’t want the future application of this opinion to irrationally restrict the ability of innovators to protect inventions that lead to medical breakthroughs.

However, not everyone agrees that innovation will be harmed. Mary Beth Tung, a patent attorney at Davis, Agnor, Rapaport and Skalny in the US and former biotechnology patent examiner for the PTO, says that if the decision had gone the other way, it would have harmed future innovation. She envisages a scenario where this case would have set an overly-broad precedent for patenting ‘purely mental processes’ or ‘inherent characteristics’.

Meanwhile, the American Medical Association (AMA) had applauded the decision. The chairman of the AMA’s board, Robert Wah, suggested that if the Prometheus patents had remained in force, physicians would have encountered a ‘vast thicket of exclusive rights’ that would prevent them from considering all relevant scientific information when reviewing diagnostic test results. ‘This is a clear legal victory that ensures critical scientific data remain widely available for sound patient care and innovative medical research,’ Wah said in a statement.

The ACLU argued that these patents on methods of correlating blood test results and drug toxicity would prevent physicians from considering whether to change a patient’s treatment in light of blood test results. But Shubin calls such concerns ‘misplaced’, saying doctors are not in the firing line. He emphasises that they are not interested in suing the doctors. Rather, he says his clients want to ensure that generic companies don’t bring a medical test to market that they are in the process of developing.

Disagreements aside, most stakeholders say that it will be up to Congress to provide the clarity needed to address the confusion caused by the court’s ruling.

Rebecca Trager