Under what circumstances is injection a prohibited surgical method? Views of the EPO Enlarged Appeal Board in Treatment by surgery/MEDI-PHYSICS G 0001/07 . Opinion
From Paul Cole
The present proceedings resulted from a referral in decision T 0992/03 relating to EP-A-1066537. That specification was concerned with magnetic resonance methods for imaging the pulmonary and/or cardiac vasculature and evaluating blood flow using dissolved polarised 129Xe. Representative claims presented to the Appeal Board are set out below
1. A method for MRI imaging the pulmonary and/or cardiac vasculature using dissolved-phase polarized 129Xe, comprising the steps of:
positioning a patient in an MRI apparatus having a magnetic field associated therewith;
delivering polarized 129Xe gas to a predetermined region of the patient’s body, the polarized gas having a dissolved imaging phase associated therewith;
exciting a predetermined region of the patient’s body, having a portion of the dissolved phase polarized gas therein with at least one large flip angle RF excitation pulse; and
acquiring at least one MR image associated with the dissolved phase polarized gas after said exciting step.
6. A method according to any of Claims 1 to 5, wherein
said delivering step includes having the patient inhale the polarized 129Xe gas into the lungs, the 129Xe having a gas phase resonance which is higher than the dissolved-phase resonance, and wherein at least a portion of the 129Xe gas enters into the pulmonary vasculature in a dissolved-phase, and wherein at least a portion of the dissolved-phase 129Xe then enters the blood stream with an associated perfusion rate.
22. Use of 129Xe for the preparation of a hyperpolarized imaging agent for use in methods of treatment or diagnosis involving performance of the method as described in any one of claims 1 to 21.
The Appeal Board held that the claimed subject matter did not fall within the diagnostic method exclusion because the claimed steps were confined to the examination phase and did not include steps considered constitutive for making a diagnosis. However the claimed method covered administration of polarised xenon into the heart by injection, and the method was intended to be used inter alia for providing real-time feedback during surgery. Existing case law of the Appeal Boards had held that introduction of a catheter into the pericardial pace was an excluded method of surgical treatment (T 0035/99; see also T 0182/90 as to methods of injection), but that applying radiation to the body for the purpose of cosmetic removal of hair was not excluded (T 0383/03). Issues arising in the appeal to the Enlarged Board included whether it was possible to exclude the administration step (“pre-delivered contrast agent”) or whether the claim would be allowable if the administration step were defined at a higher level of abstraction (“administering a contrast agent”).
In particular, the Appeal Board considered that clarification of the term “treatment by surgery” was required and referred to the Enlarged Board the following questions:
1. Is a claimed imaging method for a diagnostic purpose (examination phase within the meaning given in G 1/04), which comprises or encompasses a step consisting in a physical intervention practised on the human or animal body (in the present case, an injection of a contrast agent into the heart), to be excluded from patent protection as a “method for treatment of the human or animal body by surgery” pursuant to Article 52(4) EPC if such step does not per se aim at maintaining life and health?
2. If the answer to question 1 is in the affirmative, could the exclusion from patent protection be avoided by amending the wording of the claim so as to omit the step at issue, or disclaim it, or let the claim encompass it without being limited to it?
3. Is a claimed imaging method for a diagnostic purpose (examination phase within the meaning given in G 1/04) to be considered as being a constitutive step of a “treatment of the human or animal body by surgery” pursuant to Article 52(4) EPC if the data obtained by the method immediately allow a surgeon to decide on the course of action to be taken during a surgical intervention?
The above questions were answered in an 80 page opinion of the Enlarged Board handed down on 15 February 2010.
The Enlarged Board reaffirmed the position in G 0001/04 that any therapeutic or surgical feature in a method claim causes that claim to fall under the prohibition, and “surgery” is not to be interpreted as limited to surgical methods pursuing a therapeutic purpose. It could not give an authoritative once and for all definition of “surgery” since the scope of what is regarded as surgery may change over time, and the relevant criterion should be handled on a case by case basis. However, in answer to the first question, a claimed imaging method in which, when carried out, maintaining the life and health of the subject is important and which comprises or encompasses an invasive step representing a substantial physical intervention on the body which requires. professional medical expertise to be carried out and which entails a substantial health risk even when carried out with the required professional care and expertise, is excluded from patentability as a method for treatment of the human or animal body by surgery pursuant to a.53(c) EPC.
In response to the second question, the claim cannot be left to encompass an embodiment which is excluded by a.53(c). Omission of the excluded step should be considered on a case by case basis, but e.g. claims to operation of devices without requiring a surgical step have been held allowable, see T 0245/87, T 0789/96 and T 0329/94, compare T 0082/93. Expressions such as “predelivered” and “preimplanted” have been employed to make clear that the feature pertaining to that step was not part of the claimed invention. However, the remaining requirements of the EPC and in particular a.123(2) and in opposition cases a.123(3) must still be fulfilled.
As regards the third question, a claimed imaging method does not fall within the prohibition merely because during a surgical intervention the data obtained by the use of the method immediately allows a surgeon to decide on the course of action to be taken during the surgical intervention.
It will be appreciated that the function of the Enlarged Board is not in itself to decide the outcome of the appeal, but merely to answer the legal questions put to it by the referring board. The case will now be returned to that board, who will have to decide in the light of the answers given and any amendments filed by the applicants what claims might eventually be allowed.
The present decision provides useful clarification of the relevant law, but probably does little more than to provide more authoritative support for the general approach already adopted by the EPO. It is believed that the number of applications where the outcome will be materially different as a result of the present decision is likely to be small. However, it will be interesting to see what claims are eventually allowed in this case.
The prohibition under the EPC is to surgical methods rather than surgical apparatus so that in a situation such as the present it may be desirable to present apparatus claims, in this case apparatus for MRI imaging including firstly apparatus for administration of 129Xe to the human body and secondly MRI apparatus configured to supply exciting pulses with a large flip angle and to produce a resultant MRI image. The argument could then be that there would be no motivation to bring together these pieces of apparatus but for the discovery of the new imaging method. For an example of this approach compare the granted claims in EP-B-0436717 (Maddox, Cobe Lab) with the granted claims of the equivalent US-A-5474772, for a more detailed explanation see Fundamentals of Patent Drafting, Paul Cole, CIPA, London, 2006 at pp. 218-222.
The use claim has not been considered by the Enlarged Board, but it would appear in principle to be allowable. The recitation of methods of treatment or diagnosis merely specifying performance of the previously defined method may be too general, however, and it would be expected that the EPO would require further definition characteristic of potential disease states e.g. for the purpose of providing clinically useful images of the left and right pulmonary veins and associated capillaries, the left atrium and left ventricle, the myocardium, the ascending aorta, the coronary arteries, the aortic arch, the descending aorta, the left and right subclavian arteries, and the left and right carotid arteries as recited in the description of the application.