Substance or device - a distinction without a difference?

In the wake of the UK Supreme Court decision in Warner-Lambert v Actavis (IPKat post here), second medical use claims have received considerable attention from the IP commentariat. IPKat takes a look at yet another controversy associated with the claim form: the nature of the "medical products" to which they can be applied. 

Second medical use claims are designed to protect substances or compositions for use in new medical treatments. Numerous decisions of the Technical Boards of Appeal of the EPO (TBA) have confirmed that second medical use claims cannot be used to protect medical devices. However, as is so often the case in patent law, scientific advancements are beginning to blur the technical difference on which the legal distinction between medical devices and substances is based. Given the extensive R&D and clinical trials behind the use of medical devices (not just in the manufacture of the device itself), is the exclusion of medical devices from second medical use and/or SPC protection desirable? Is this a further reason to rethink the form and scope of second medical use claims?

In any consideration of second medical use claims, it is always useful to recall their origin and purpose.

History of the second medical use claim

The exclusion of medical methods from patentablity was included in the first draft of the EPC (EPC 1973, Article 52(4)). Such methods were considered to lack industrial application, so as not to hamper the freedom of medical or veterinary practitioners (G 01/07).

The original EPC 1973 provision also stated that the method of treatment exclusion should not "apply to products, in particular substances or compositions, for use in any of these methods". The wording of EPC 1973, Article 52(4) was initially problematic from a claim drafting point of view. This was because a claim directed to a known product is not normally considered novel. Such a claim is judged to lack technical contribution (G 02/88). Protection for a known substance or composition for use in a new treatment were thus sought using a "use" claim and not a product for use claim, the so-called Swiss-style claim form, i.e. "use of a substance in the manufacture of a medicament for the treatment of disease Y" (G 5/83). The word "manufacture" in the Swiss-style claim was to provide the claim with industrial application and thus overcome the EPC 1973, Article 52(4) exclusion of methods of treatment.

However, the "manufacture step" of Swiss-style claims was considered an unnecessary legal fiction (G 02/08). EPC 2000 was thus drafted to allow second medical use claims for substances and compositions. Particularly, Articles 54(4) and 54(5) EPC specify that a known substance or composition for a new medicinal use is considered novel. This leads to the second medical use claim form: "Drug X for use in a method of treatment". A known substance or composition for a known medical use is accepted as novel in view of the significant R&D required to develop a new therapeutic use, even for a known drug. As an extra hurdle to patenting second medical uses, it is necessary for the applicant for the patent to plausibly demonstrate the claimed new use.

Therefore, in Europe, methods of treatment are not considered patentable because patents for methods of treatment would restrict the freedom of medical practitioners. Furthermore, a known (non-medicinal) product for a new use is not considered novel, because disclosure of the use does not require the inventor to disclose any technical contribution. However, in view of the need not to unduly restrict the pharmaceutical industry, known drugs for a new use are patentable, provided that the new use is plausible.

Interestingly, the Enlarged Board of Appeal recognized in G 02/08 that the rights conferred on the patentee by second medical use claims "could...lead to possible restrictions on the freedom of medical practitioners to prescribe or administer generics. However, in view of the clear provisions of Articles 53(c), second sentence, and 54(5) EPC and the intention of the legislator, the Enlarged Board has no power to broaden or reduce in a praetorian way the scope of these provisions. If deemed necessary, the freedom of medical practitioners may be protected by other means on the national level" (e.g. as providing an exception to infringement for medical practitioners performing treatment).

What is a "substance or composition"?

The phrase "substance or composition" in Articles 54(4) and 54(5) EPC traces its origin back to EPC 1973, Article 52(4), which stated that the exclusion of medical methods should not "apply to products, in particular substances or compositions, for use in any of these methods".  A medical device if new and non-obvious, can be protected by a product claim directed to the technical features of the device itself.

Nanobot - substance or device?
"Substance or composition" is not defined in the EPC. The Enlarged Board of Appeal decision that established the Swiss-style claim form also did not explicitly define the phrase (G 5/83). In T 2003/08 (Edwards Lifesciences), the TBA never-the-less took the view that it was evident from the "whole reasoning" of G 5/83 that "substance or composition" referred to an active agent in medical use. G 5/83 makes reference, for example, to "the active substance or composition" and "active material"). The active agent is the ingredient that provides the therapeutic effect in a medicament, as opposed to an excipient or the medicament's packaging. In T 2003/08 the TBA concluded that, in order to determine whether or not a "substance or composition" is used in a treatment, the following must be established:

(a) the means by which the therapeutic effect is achieved and 
(b) whether that which achieves the therapeutic effect is a chemical entity or composition of chemical entities.

Physical versus Chemical

The latest published TBA decision to address the meaning of "substance or composition" was T 1758/15. The case at issue was an appeal of a decision from the Opposition Division to revoke EP 1536746. The granted patent related to a filler material that is injected prior to radiation therapy. The patent describes the use of the filler material to reduce the side effects of radiotherapy. Particularly, the filler material can be injected into the space between two tissues, so as to reduce the amount of radiation that passes from an irradiated target tissue to secondary tissues.

Claim 1 of the patent was drafted in second medical use form:

A biocompatible, biodegradable filler material for injection and for use in radiation treatment whereby the filler is injected to a space between a first tissue of a body and a second tissue, and whereby the first tissue is treated by radiation whereby the filler within the space reduces passage of radiation into the second tissue.

The Proprietor argued that the filler material had the properties of a substance or composition. Given that the use of the filler material was new, it was argued, the claim should therefore be considered novel under Article 54(5).

Applying the principle proposed in T 2003/08 (Edwards Lifesciences), the TBA asked (a) how the therapeutic effect of the filler material was achieved ("the principle mode of action"), and (b) whether the effect was achieved by a chemical entity or composition of chemical entities. The TBA determined that the therapeutic effect was achieved by "physical displacement of the sensitive tissue". Particularly, the specification showed that the filler was effective by increasing the distance and occupying a volume, i.e. "by a physical effect of the accumulated mass and not due to its chemical constitution...The spacing effects were present for any filler material, which further underlined that the effect was a physical one, independently of the particular chemistry of the filler". The TBA thus concluded that the filler was a device and not a substance or composition.

The proprietor had argued that the filler material, aside from providing the "filling" function, was also biocompatible, biodegradable and injectable. All of these properties, it was argued, contributed to the therapeutic effect. A biodegradable material, for example, removed the need for surgical removal of the material. It can also be noted that producing and demonstrating the effects of a material that is suitable for injection, is non-toxic, biodegrades and has advantageous therapeutic properties, is not a trivial task.

However, the TBA noted however that biodegradability and biocompatibility were typical device features. They reasoned that "[i]f these effects were to be taken into account as prophylactic effects of the material, indirect second medical use protection of any device would be possible, contrary to the wording of the EPC". The TBA therefore agreed with the Opposition Division that the claim was not novel.

The view of the TBA in T 1758/15 regarding the definition in Articles 54(4) and 54(5) EPC of "substance or composition", can therefore be summarized as a product that achieves a direct therapeutic effect by a chemical, as opposed to physical, interaction with the body.

Tissue Scaffold
But is the distinction between physical and chemical modes of action, a distinction without a difference? Is there a distinction in terms of the social and ethical considerations for patentability (i.e. the purported justification of the second medical use claim)? Consider, for example, the case of magnetic particles used for targeted therapeutic heating of tumors. Given that heating is considered a "physical effect", these particles may not be considered substances or composition for use in medical treatment. However, the discovery, development and regulatory approval required for such particles is equivalent to that of drugs. Consider also the case of organic and synthetic scaffolds used in tissue generation. These scaffolds may be implanted directly into the body, and interact both physically and chemically with regenerating cells. It can be unclear whether it is the shape of the scaffold or its chemical composition that is responsible for a particular therapeutic effect. Is such a scaffold a "substance or composition", or a "device"? Again, the R&D and regulatory requirements for medical products based on tissue scaffolds can be considerable.

A note on Supplementary Protection Certificates

Whilst the process for regulatory approval of medical devices is not as stringent as that for medicinal products, medical devices containing active ingredients still face significant regulatory requirements. However, it was recently confirmed by the CJEU that SPCs are also not available for medical devices (Case C‑527/17).

The SPC request in Case C‑527/17 was on the basis of Boston Scientific's patent EP (DE) 0681475. The original granted patent (appeal from the opposition pending), was granted with Swiss-form claims for the use of cytochalasins for the manufacture of a sustained release dosage form for preventing stenosis. According to Article 2 of the SPC Regulation (EC) 469/2009, a product is only eligible for SPC protection if it has been approved in accordance with the Medicinal Products Directives 2001/83/EC (MPD). MPD defines a medicinal product as "[a]ny substance or combination of substances presented as having properties for treating or preventing disease in human beings" (Article 1(2)).

Boston Scientific had obtained product approval for their coronary stent under the Medical Device Directive (93/42/EC) (MMD) but not under the MPD. The MDD defines a device as "any instrument, apparatus, appliance, material or other article"..."used for human beings for the
purpose of diagnosis, prevention, monitoring, treatment or alleviation of disease"..."that does not achieve its principal intended action in or on the human body by pharmacological, immunological or metabolic means". The CJEU ruled that an SPC cannot be granted for a device, even if the device comprises an active substance for which MPD approval has been obtained.

In summary, there is currently a clear negative answer to the question of whether it is possible to patent a new medical use of a known device. However, the boundary between substance and device is not perhaps as clear cut as it may first appear. In T 1758/15 the TBA reduced the distinction between substance and device to a difference between a physical and a chemical mode of action. However, the existence of second medical use claims is due to a recognition of the importance for society of inventions relating to methods of treatment. Second medical use claims thus reward the time and money spent in developing and bringing to market a product for a first and then further medical use. Given this background, should similar protection not also be afforded to any inventive medical treatment, regardless of whether it is reliant on the chemical or physical mode of action of a product?

by Rose Hughes
Substance or device - a distinction without a difference? Substance or device - a distinction without a difference? Reviewed by Rose Hughes on Thursday, December 20, 2018 Rating: 5


  1. Another interesting example might be a surgical tissue adhesive. Certainly a substance or composition, and bonding would involve a chemical reaction, but I suspect it might struggle with a second medical use claim if it is seen as achieving its therapeutic effect by physically holding tissue together.

  2. One wonders why if the terms substance or composition were intended only to comprise materials having a therapeutic effect, the law makers did not introduce "therapeutic" into the article. In my opinion, this really needs a G decision to clarify but the chances of a board issuing a contrary opinion seem remote.

  3. Decision T 758/15 is the result of a long line of decisions in which the BA always concluded that the second medical use claims are only available for substances and compositions and not for devices. The analysis of the BA is very convincing in my view.

    Rather than to reduce the discussion to a mode of action either of chemical or physical nature, it appears much more appropriate to decide whether the “product” at stake has an effect of the metabolism of the human or animal body. In the broadest sense it can be considered as being chemical, but the chemistry at stake takes place within the human body. Furthermore, through its action on the metabolism, the product=substance=composition disappears during its action. This cannot be said for a device, even if it is biodegradable. In such a case, it disappears, but without any action on the metabolism.

    Claims to a first or further medical use for a known “product” are a big exception to the novelty concept as it is handled in the Convention and by the EBA/BA. As such it should remain an exception. Any purpose related novelty/inventive step for known products is to be avoided. It would unnecessarily introduce confusion.

    At the end of the blog, the suggestion is made that “any inventive medical treatment, regardless of whether it is reliant on the chemical or physical mode of action of a product” should be opened to patentability. In other words, the exception under Art 53,c should be removed. I beg to disagree as this would be in clear contradiction to the intention of the legislator, be it in 1973 or in 2000. In 2000, the EPO had proposed the deletion of Art 52(4) EPC1973, but the contracting states disagreed and its content was merely transferred into Art 53, c).

    There are also further considerations which lead to the conclusion that medical treatment, or a method for treating the human body should not be patentable.

    Inventions are there to solve a “technical” problem. Can restoring health or alleviating pain merely be a “technical” problem? With a "true" technical process, be it a process of manufacture or a way of using a device, the correct input values always lead to a reproducible result. In the medical field, the expected result does not always occur, the human or animal body has his own laws.

    When discussing the patentability of medical methods, we should also keep in mind that the doctor is only obliged to practice his “skills” or his “art”. He cannot be made liable for the expected result, i.e. the recovery of the patient.

    There is no need for a remittal to the EBA as the case law of the BA is very clear and not diverging. OK for substances or compositions but not for devices.

    By the way there is only one decision in which a BA patented a known device when used in medical method. See T 138/95, where a BA patented a known aerosol producing device when accepting a Swiss-type claim for a new therapeutic way of administering growth factors or cytokines:

    “Use of a polypeptide selected from growth factors and cytokines for the manufacture of a device for delivering to the blood stream of a patient a therapeutic dose of the peptide by systemic delivery by pulmonary absorption said device comprising reservoir means (8) for storing the polypeptide; a therapeutic dosage form of the polypeptide disposed in the reservoir means; dispersing means (4-7) for forming in a gas a suspension of particles comprising the polypeptide wherein greater than about 15% of the particles have a mean average diameter of about from 0.5. µm to 4 µm; means (1-3) for transporting the polypeptide to the dispersing means and means (9-12) for delivering the particle suspension to the alveoli of the patient's lungs”

  4. In response to 'Interested Observer':

    The present exclusion of medical devices from medical use claims is not logical, and essentially prevents certain technologies from patent protection without any good reason. Devices can of course be limiting features in a medical use claim if a therapeutic substance is involved. In such a scenario an improvement in the device which is novel and inventive could give rise to an acceptable novel and inventive medical use claim, even though the same therapeutic substance was involved.

    This ends up being a situation where clever drafting gets a patent, and not an underlying policy objective

  5. Dear 123,

    You seem to have forgotten that the novelty system wished by the legislator and developed by the case law of the BA is an absolute one.

    A device does not become new because a new use has been devised for it. The only exception is for substances and compositions relating to medical uses. As an exception it should be handled sparingly, and rightly so.

    A new, medical use use, of a known device cannot be protected due to the prohibition under Art 53, c).

    You seem also to mix device, use and substance. A coated stent will remain a device. If it is patentable, then question of the protection of its use is moot. On the other hand, the coating might also be patentable, but in any case the use of the coated stent inside veins or arteries will never be patentable. And it is good so.

    This has nothing to do with clever writing of claims.

  6. @123:

    No clever drafting is needed to patent a (medical or non-medical) device which is novel and inventive.

    As to methods of treatment, if a new and inventive method of treatment involves the administration of a known "substance or composition", then (purpose-limited) protection can be obtained for that substance or composition.

    If the same method of treatment also involves the use of a known medical device, then no protection can be obtained for that known medical device. This was a deliberate decision by the legislator as can be seen from the wording of Articles 53(c) and 54(4) and (5) EPC.

    As always, there will be cases in which discussion is possible about whether a particular product is a "substance or composition".

    Since this was a decision by the legislator, it is irrelevant whether the exclusion of protection for known (or in itself obvious) medical devices is logical. (In my view it is logical: a "substance or composition" with a therapeutic effect is mandatorily sold with a label identifying the purpose, which turns the limitation on purpose into an objective property of the product+label. The situation is different for medical devices.)

  7. Question from a junior: Should not the second medical use patents involve only the USE?
    As said above, a new use does not make the product new. Even if it is a substance/composition.
    I believe it would be more simple if second medical use just allowed use claims.
    What am I not understanding from my junior point of view?

  8. @Fabricio:
    Article 53(c) EPC does not allow the patenting of methods for treatment, which is what a use claim would be.

    To compensate, the legislator initially introduced what is now Article 54(4) EPC and, with EPC 2000, added Article 54(5) EPC. These provisions allow the patenting of a known "substance or composition" for a new first or second medical use. In these particular cases (only), a new use does make the product new (and potentially inventive).


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