In the last century, innovations in the life sciences have allowed for treatment and prevention of numerous diseases and disorders, enabling higher life expectancy and improved quality of life. It is well-recognised that development of new therapeutics requires an enormous investment of resources including time and money. For example, a study conducted in 2014 estimated that the average cost of bringing a new drug to market exceeded US$2.5 billion.[1] The availability of a limited monopoly in the form of patent protection provides encouragement for commercial entities to expend these resources, and expose themselves to substantial risk, in order to attempt to develop new therapeutics.[2]

Most jurisdictions offer some form of patent protection for human therapeutics. However, the specific manner in which an invention in this field of technology can be claimed in a patent varies considerably. In this respect, practice in Australia includes some distinctive features, which we discuss here. This article forms the first part of a two-part comparative piece, addressing patent protection for human therapeutics in a range of Asia-Pacific jurisdictions.

Therapeutic Claiming

Depending on legal practice in a particular jurisdiction, various claiming strategies may be available to seek patent protection for inventions directed to therapeutic treatment of humans. The most direct approach to protecting a method of treatment is a claim to the method itself. Such ‘method of medical treatment’ claims may be patentable where (i) they relate to use of a new product (even where the method steps are conventional) and/or (ii) involve new method steps. Examples of the latter can include treatment of a new disease with a known drug, and methods directed to new treatment regimes, e.g. dosage amounts and/or timing.[3] Notably, however, direct claiming of methods of medical treatment is precluded in many jurisdictions, either by legislation, or case law precedent.

Where a therapeutic product can be shown to be patentable itself, a claim to this product will generally be permissible, even if claims to treatment using the product are not permitted in a given jurisdiction. Thus, where a new drug or medical device is developed, protection of the therapeutic use thereof will normally be obtainable by way of product claims.[4] Nevertheless, in many instances the contribution of an invention directed to therapeutic treatment may be use-related. This is particularly the case for therapeutically active compounds. For example, it may only be demonstrated that a known compound is therapeutically useful long after the discovery of the compound itself. Similarly, a compound that is known to be useful for treating certain conditions may later be demonstrated to be effective for treatment of other conditions. Under these circumstances, claims to the known product itself, i.e. regardless of use, will not be obtainable. However, even in jurisdictions where method of medical treatment claims are precluded, it may be possible to obtain protection if another mechanism for claiming a new use of a known product is available.

The Approach in Australia

Method of Medical Treatment Claims

As noted above, claims to methods of medical treatment are impermissible in many jurisdictions. However, it has been clearly established that such claims are allowable in Australia; in Apotex Pty Ltd v Sanofi-Aventis Australia Pty Ltd [2013] HCA 50, a majority of the Australian High Court found that methods of medical treatment of the human body was patentable subject matter under Australian law.[5]

Given the ability to claim methods of medical treatment in Australia, it is further notable that the Australian Patents Act[6] features provisions regarding ‘infringement by supply’, in regard to use of a product for a particular claimed purpose. Specifically, Section 117 states that:

If the use of a product by a person would infringe a patent, the supply of that product by one person to another is an infringement of the patent by the supplier unless the supplier is the patentee or licensee of the patent.

Importantly, these provisions can allow for a finding of infringement of a medical treatment claim against a manufacturer of a composition or medical device, despite the direct scope of the claim relating to steps generally performed by a physician or a patient. Notably however, making out infringement by supply can be relatively involved, as exemplified below with reference to the recent case of Otsuka Pharmaceutical Co., Ltd v Generic Health Pty Ltd (No 4) (Otsuka).[7]

Use-limited Product Claims

As alluded to above, in some jurisdictions, use-limited claiming of therapeutic products is possible, allowing for a position to be obtained in relation to a product, such as a drug,[8] used for a specific purpose. Although claims for this purpose are allowable in Australia, Australian practice is somewhat unusual in this respect, for the following reasons.

Under Australian practice, claims in the form “product X for [or for use in] purpose Y” are allowable, and can be used to claim a therapeutic use. However, unlike in some other jurisdictions, notably Europe,[9] therapeutic claims in such a format are considered limiting only to the extent that the product must be ‘suitable for’ the recited purpose. The effect of this is that if a product (e.g. a drug) is known, an Australian claim directed to the drug ‘for’ or ‘for use’ in a particular therapeutic purpose will be considered to lack novelty (as it will be considered that the known drug was inherently suitable for the recited purpose).

Australian law also allows for claiming in the unconventional form “product X when used for purpose Y”, with such claims given a construction that is particular to Australian practice. Specifically, as per the High Court decision in Wellcome Foundation Ltd v Commissioner of Patents[10] such claims are considered ‘disguised process claims’, having essentially equivalent scope as a method claim directed to the recited use. As a result, claims in this form can confer novelty for a new use of a known product, including a therapeutic product, in Australia. However, as for a method of medical treatment claim, a therapeutic use claim in “when used for” format will only be directly infringed by use of the product in the claimed manner, i.e. the claim will not be considered directed to the product per se.[11]

Yet another approach for claiming a particular use of a therapeutic product is available in Australia by the use of ‘Swiss-type’ claims. A Swiss-type claim is generally drafted in the form “Use of compound X in the manufacture of a formulation for the treatment of condition Y” (or similar). The scope of Swiss-type claims has been subject to limited assessment in Australia. However, these claims have been generally assumed to be directed to manufacture when there is an intention of use of the formulation for the recited purpose, in accordance with construction in other jurisdictions, and as such, Swiss-type claims are currently treated as use-limited in Australia. Notably however, in Otsuka (referred to above and discussed further below) a single judge of the Australia Federal Court has recently commented on interpretation and infringement of Swiss-type claims.

Another relevant aspect of Australian law in regard to use-limited claiming is the approach to allowability of ‘first medical use’ claims. Such claims, permissible in Europe, allow for all medical uses of a known compound to be claimed, upon first recognition that the compound has at least one medical use. Due to the particularities of Australian law in regard to sufficiency, first medical use claims were achievable for applications for which examination was requested prior to 15 April 2013. However, under the provisions of the ‘Raising the Bar’ Act of 2012,[12] the current approach is that a use-limited product claim will only be considered supported by the disclosures of a patent specification if it could reasonably be expected that the product would be effective for the recited purpose. In practice, this precludes claiming all possible medical uses of a compound, as these claims will be objected to for lack of support.[13] As such, first medical use claims in the form available in Europe are not likely to be obtainable in Australia.

Otsuka Pharmaceutical Co., Ltd v Generic Health Pty Ltd (No 4)

As referred to above, in Otsuka, a single judge (Justice Yates) of the Federal Court has recently commented on the interpretation of Swiss-type claims in Australia. An opinion on the comparative requirements for infringement of Swiss-type and method of medical treatment claims was also provided by his Honour, notwithstanding that the assessed claims were ultimately found invalid in this case. The decision in Otsuka focused on claims relating to aripiprazole (defined by a specific structural formula) for the treatment of schizophrenia under certain conditions.[14]

In regard to the interpretation of Swiss-type claims, his Honour opined that, ‘an invention defined by a Swiss type claim is appropriately characterised as method or process’, rather than as a claim to the product itself. This generally accords with the interpretation of Swiss-type claims in other jurisdictions. It would also appear to clearly support the current approach to examination in Australia, wherein such claims are considered use-limited. This is because, where the claim is considered a method, the recited use is a step of that method that must be performed in order to be encompassed by the scope of the claim.

In regard to infringement, his Honour’s position was that the direct infringer of a Swiss-type claim was the manufacturer of the composition (which again accords with prior assumptions under Australian practice, and the approach in many other jurisdictions). His Honour went on to state that, had the claims been valid, to establish infringement the evidence must demonstrate that the alleged infringing medicament, was ‘effective in the treatment’ of the recited conditions as per the claim.[15] In this regard, his Honour took into consideration that the alleged infringer (the Respondent, Generic Health) had sought marketing approval for use of its products containing the claimed compound for treatment of schizophrenia, and considered that this included all types of schizophrenia, including that recited in the claim.[16] On this basis, it was opined that, had the claims been valid, Generic Health’s products would have infringed the claims.

Notably, to attempt to avoid possible infringement, Generic Health proffered an undertaking that it would not advertise or promote its products for the specific use recited in the Swiss-type claim being assessed. In response, his Honour stated that, in assessing infringement of Swiss-type claims, ‘[t]he question is whether, objectively ascertained, the medicament that results from the claimed method or process is one that has the therapeutic use defined in the claim’. His Honour went on to state that ‘[t]he question is not really about how the alleged infringer markets its product, although, plainly, its conduct in that regard may well assist in determining, objectively, whether the accused product has the claimed therapeutic use’.[17]

It will be apparent from the above that there is no clear indication in Otsuka that his Honour considers a manufacturer’s intention regarding the use of a composition to be of central significance to infringement. Rather, his Honour could be interpreted as stating that a product will infringe a Swiss-type claim so long as it has therapeutic use that falls within the scope of the claims. However, if this was indeed the intention of his Honour, it would raise serious questions regarding the relative scope of novelty and infringement of Swiss-type claims under Australian law.

In this respect, as noted previously, current practice in Australia (as in other jurisdictions) is that Swiss-type claims will be considered novel if directed to a new therapeutic use of a known compound. This appears entirely consistent with his Honour’s characterisation of Swiss-type claims as method or process claims, as explained above. However, if his Honour was suggesting that it need only be demonstrated for infringement of a Swiss-style claim that a product be effective for the claimed use, rather than intended for that use, this would appear in direct conflict to the current approach to novelty. By way of elaboration, under these circumstances, a Swiss-type claim for a new use could be granted for a composition that was previously known, with the previously known composition then infringing the claim by virtue of being effective for the new use. It would appear very unlikely that his Honour was, in fact, advocating in Otsuka for such a situation to arise. Nevertheless, further clarification on this issue would be highly desirable.

It is noteworthy that the decision in Otsuka comes at a time when similar issues regarding Swiss-type claims are receiving attention in Europe and the UK. In this respect, in the UK, the Court of Appeal decision in Warner-Lambert Company, LLC v Actavis Group Ptc EHF & Others[18] (Warner Lambert) has established that infringement of a Swiss-type claim by a manufacturer requires that the manufacturer knows (including constructive knowledge) or can reasonably foresee that the medicine would ultimately be used for the claimed method. It will be appreciated that such an approach reconciles issues in relation to novelty and infringement of use-limited Swiss type claims as described above, and is consistent with current examination practice in Australia.

Infringement of Method of Medical Treatment Claims

The decision in Otsuka also provides an exemplification of an assessment of infringement by supply with respect to a method of medical treatment claim under Australian law. Specifically, a method claim which recited corresponding features to the Swiss-type claim discussed above was also assessed by his Honour for infringement in this case.[19]

In considering possible infringement of the method of medical treatment claim, his Honour first addressed the issue of whether aripiprazole compounds should be considered a ‘staple commercial product’. In this regard, if the compounds were not considered to be a staple commercial product, under Australian law, where it was demonstrated that Generic Health (as a supplier) had ‘reason to believe’ that their product might be used in an infringing manner, this would be sufficient to make out infringement by supply.[20] In contrast, if it was held that aripiprazole was a staple commercial product, infringement by supply would only be found if either the product was only reasonably capable of the infringing use,[21] or it could be demonstrated that Generic Health has supplied instructions or inducement to use the product in an infringing manner.[22]

Despite submissions from Generic Health to the contrary, his Honour found that aripiprazole was not a staple commercial product. As such, the issue of potential infringement turned upon whether Generic Health had reason to believe that the product supplied would be put to the infringing use. In view of substantial evidence provided by both parties, his Honour ultimately concluded that a ‘not insignificant’ number of Australian clinicians would use Generic Health’s products for treatment in accordance with Otsuka’s method of medical treatment claim. It was therefore held that Generic Health did have reason to believe that this would occur, and that infringement by supply could apply in this case (had the claim been valid).

Although it was ultimately found that infringement could have applied in Otsuka, it will be apparent that his Honour’s decision relied upon a somewhat subjective characterisation that the product at issue was not a staple commercial product,[23] and subsequent determination of whether it would reasonably be expected that the Respondent’s product would infringe, based on expert testimony from both sides. This serves to highlight the potential complexity of making out infringement by supply of a method of medical treatment claim in Australia.

Conclusion

Given the tremendous investment required for the development of new therapeutics, and the key role of patent protection in encouraging this investment, obtaining suitable patent protection for therapeutic inventions is of critical importance.

As discussed above, Australia offers a flexible approach to therapeutic claiming, with the ability to claim as (i) ‘product for purpose’ (limiting only to the extent that the product must be suitable for the purpose); (ii) ‘product when used for purpose’ (use-limited but construed essentially as a method claim); and (iii) in Swiss-type format. Notably however, given Yates J’s comments in Otsuka, clarification of the requirements for infringement of Swiss-type claims in Australia would be desirable.[24] It is suggested that the approach to infringement established in the UK case of Warner Lambert (discussed above) is consistent with current practice and reconciles potential issues in relation to novelty and infringement of Swiss-type claims.

Notwithstanding this issue, in view of the idiosyncrasies in relation to therapeutic claiming described herein, preparing claims guided by a clear understanding of local practice is strongly beneficial for obtaining optimal protection for therapeutic inventions in Australia.

Part II of this article will be released on Tuesday 29th November.