Chapter excerpt from the ebook MedTech IP: Lessons and Strategies for Success - view all chapters here.
The European Patent Convention (EPC) decrees that European patents shall not be granted in respect of:
"methods for treatment of the human or animal body by surgery or therapy and diagnostic methods practised on the human or animal body..."
With some variations, similar provisions apply in other jurisdictions all over the world. This is often understood to be a significant barrier to large swathes of patent protection within MedTech circles, but is it really a barrier?
It is important to understand that this exclusion relates only to certain methods, and not to medical devices and products. In fact, there are actually more European patent applications published in the areas of surgery and diagnosis than in any other area of MedTech. This is illustrated in the following graph, which shows the number of published European patent applications over recent years for the top 10 sub-sectors in the MedTech industry.
As you can see in the graph: not only are areas of surgery and diagnosis at the top of the charts, but the number of patent applications in these areas have actually been increasing over recent years.
Let’s see how all this was made possible…
Born on 29 July 1898 into a Polish-Jewish Orthodox family, Isidor Isaac Rabi was a close friend of Robert Oppenheimer, the well-known American physicist responsible for developing the first atomic bomb during World War II. In the 2023 film Oppenheimer, Dr Rabi can be seen testifying on behalf of Oppenheimer at the Atomic Energy Commission's controversial security hearing in 1954 that led to Oppenheimer being stripped of his security clearance.
After growing up in New York and completing his PhD, in 1927 Isidor Rabi headed to Europe where he spent two years immersing himself in the new field of quantum mechanics, working with such giants as Bohr, Pauli, and Heisenberg. He gained a reputation for reinventing experiments to seek insights that brought him, he wrote, “nearer to God.” “You’re wrestling with a champ,” he would tell his physics students. “You’re trying to find out how God made the world, just like Jacob wrestling with the angel.”
Isidor Rabi returned to the US, and in 1937 he predicted that atomic nuclei aligned by a magnetic field and subject to a pulse of radio waves would absorb this pulse and flip their spin. When their spin flipped back they would re-emit the pulse, which experimenters could detect. Importantly, different kinds of materials absorbed and re-emitted pulses at different frequencies, thus allowing scientists to distinguish between materials, even within solids.
Isidor had discovered nuclear magnetic resonance (NMR), for which he won the 1944 Nobel Prize, and this discovery formed the basis of magnetic resonance imaging (MRI), which identifies atoms by how they behave in magnetic fields and produces very clear images within the body.
After Isidor Rabi's ground-breaking discovery, there have been many subsequent inventions relating to MRI imaging, leading to many patents and at least a further four Nobel prizes. Here we look at one such invention relating to the injection of a magnetic contrast agent, which will teach us something about patent law relating to surgery and diagnosis.
In July 1997 Martin Prince from Michigan filed International Patent Application No. PCT/US96/20338 for a "Method and apparatus for magnetic resonance imaging of arteries using a magnetic contrast agent." Little known to Prince at the time, his application was to help shape the course of patent law in this area, but he was also in for a long patent journey.
Prince was successful in obtaining grant of his patent application in 22 March 2000. The application was granted as European Patent No 0 812 151. However, that was not the end of the story. In Europe, granted patents can be opposed within 9 months of grant, and a notice of opposition was filed against Prince's patent by Koninklijke Philips Electronics N.V. on 19 December 2000, just three days before the 9 month deadline.
Unfortunately for Prince, the opposition was successful. In its decision revoking the patent, dispatched on 11 June 2002, the opposition division held that the subject-matter of the claims 1-11 of the granted patent was excluded from patentability because it constituted a diagnostic method practised on the human or animal body and, moreover, included a step of treatment of the human or animal body by surgery.
As noted above, the European Patent Convention (EPC) does not allow patents for certain methods practised on the human or animal body, but the exclusion applies only to methods, and not to medical devices and products.
Returning to our story, Prince appealed against the decision of the opposition division.
However, Prince's bad luck had not yet run out. It just so happened that, at the time of Prince's appeal, the President of the European Patent Office (EPO) referred a point of law to the Enlarged Board of Appeal (EBA) of the EPO concerning very similar issues as were raised by Prince's case. Following this a further similar point of law was referred to the EBA. Such referrals to the EBA are rare, and Prince was unlucky to have two such referrals which were both relevant to his patent application. The result of these two referrals was to delay Prince's own appeal by over 6 years, before oral proceedings were summoned on his appeal in 2010. Clearly, Prince had staying power, as it was by now 13 years since the filing of his original PCT application in 1997.
The EBA at the European Patent Office decides on points of law of fundamental importance, and the points of law referred by the EPO President resulted in two key decisions, G 1/04 concerning diagnostic methods practised on the human or animal body, and G 1/07 concerning methods for treatment of the human or animal body by surgery.
Prince was, on the one hand, unlucky that these decisions of the EBA caused significant delay to his own appeal, but on the other hand lucky that these decisions of the EBA were helpful to his appeal, as we shall see.
In its opinion for G 1/04 the EBA stated that the method steps to be carried out when making a diagnosis include four key steps:
- the examination phase involving the collection of data,
- the comparison of these data with standard values,
- the finding of any significant deviation, i.e. a symptom, during the comparison, and
- the attribution of the deviation to a particular clinical picture, i.e. the deductive medical decision phase.
The EBA concluded that the diagnostic methods referred to in the exclusion cited above "include the method step related to the deductive medical or veterinary decision phase, i.e. the diagnosis stricto sensu, representing a purely intellectual exercise". The EBA concluded that, in order for a diagnostic method to be excluded from patentability, the method needed to include, "the feature pertaining to the diagnosis for curative purposes as a purely intellectual exercise representing the deductive medical or veterinary decision phase", as well as the preceding steps.
In simplified terms, claim 1 of Prince's granted patent included the following steps:
"A method of imaging an artery in a region of interest
in a patient using magnetic resonance imaging and a
magnetic resonance contrast agent, the method
containing the steps of:
injecting the magnetic resonance contrast agent into a
vein remote from the artery;
monitoring the region of interest by using a series of
magnetic resonance radio frequency pulses ... ;
detecting the arrival of the contrast agent in the
region of interest ....;
generating an imaging initiation signal after detecting
the arrival of the contrast agent in the region of
interest;
collecting magnetic resonance image data in a magnetic
resonance imaging sequence in response to the imaging
initiation signal, ... and
constructing an image of said artery, using the
magnetic resonance image data, wherein the artery
appears distinct from the adjacent veins and background
tissue.
You will notice when reading this claim that it contains no step of performing a diagnosis as a result of the images obtained. In the words of the EBA in decision G 1/04, the claim does not include the "deductive medical decision phase", i.e. step 4 in the four key steps listed above. The "diagnosis stricto sensu" is missing. Rather, the claim includes only the preceding steps of gathering information which are constitutive for making the diagnosis (i.e. "monitoring ..., detecting ..., generating ..., collecting ..., constructing ...").
The appeal board had made Prince wait for decision G 1/04 of the EBA, but the wait had paid off. Prince was over the first hurdle. His method was not, after all, a diagnostic method.
However, another hurdle remained for Prince. The opposition division had revoked Prince's patent on another ground, namely that the method included a step of treatment of the human or animal body by surgery. Recall that Prince's method included the step of injecting the magnetic resonance contrast agent into a vein. Was this step of injecting sufficient to amount to a form of "surgery", as the opposition division had held?
Here, the delay in Prince's appeal again paid off. Prince benefitted from decision G 1/07 of the EBA. In that decision, the EBA held that, "Methods for retrieving patient data useful for diagnosis may require administering an agent to the patient, potentially by an invasive step like by injection, in order to yield results or at least they yield better results when using such a step. Considering this technical reality, excluding from patentability also such methods as make use of in principle safe routine techniques, even when of invasive nature, appears to go beyond the purpose of the exclusion of treatments by surgery from patentability in the interest of public health."
The EBA also consistently argued for a narrow construction of the exclusion from patentability, stating, "a narrower understanding of what constitutes by its nature a "treatment by surgery" ... is required."
Following this guidance, in Prince's case the appeal board held that:
"an intravenous injection can today be delegated by a physician to a qualified paramedical professional. This gives an indirect hint at the fact that such an injection may be considered as representing a minor routine intervention which does not imply substantial health risks when carried out with the required care and skill. It thus follows that the step of intravenously injecting a contrast agent would be ruled out from the scope of the application of the exclusion clause."
Thus, nearly 14 years after his initial filing date, and nearly 15 years after his priority date, Prince's patent was finally maintained as granted by the appeal board.
For completeness, we note that the exclusion relating to surgery relates to the nature of the treatment rather than its purpose. Therefore methods of treatment by surgery for cosmetic purposes are excluded from patentability, as well as for therapeutic purposes. The reason for this exclusion from patentability is to allow surgeons to perform surgical methods without worrying about whether their surgery may infringe a patent.
Prince's case is instructive because it teaches us something about the limits of the exclusions relating to surgical methods and diagnosis.
As for Isidor Rabi, he died at his home in Manhattan from cancer on January 11, 1988. In his last days, he was reminded of his greatest achievement when his doctors examined him using an MRI machine, made possible by his Nobel prize-winning work. The MRI machine happened to have a reflective inner surface, and he remarked: "I saw myself in that machine... I never thought my work would come to this."
In the next chapter we shall look at the other part of Article 53(c) which relates to methods for treatment by therapy - so called "therapeutic methods".
