We are sometimes asked which is the best way to seek patent protection for a new use of a known substance in Australia – by Swiss-style use claims or method of treatment claims.
Method of treatment claims typically take the format: A method of treating [medical condition X] which comprises administering to a subject an effective amount of [compound Y].
Swiss-style use claims typically take the format: Use of [compound Y] in the manufacture of a medicament for the treatment of [medical condition X].
In summary, both of the above claim types are considered to relate to patentable subject matter in Australia, but this is most clear for method of treatment claims (as Australia’s High Court has considered this issue). At least in some cases, however, it seems to be significantly easier to pursue drug manufacturers for infringement of Swiss-style use claims rather than for method of treatment claims. It is therefore preferable to include both claim types, if appropriate, in Australian patent applications. A detailed analysis of these issues follow.
Patentability
In Australia, unlike many jurisdictions, both Swiss-style use claims and method of treatment claims are considered to relate to patentable subject matter. The patentability of method of treatment claims is very clear, as in 2013 Australia’s highest court (the High Court of Australia) concluded that method of treatment claims relate to patentable subject matter (Apotex Pty Ltd v Sanofi-Aventis Australia Pty Ltd [2013] HCA 50). While the validity of Swiss-style use claims has not received the same level of judicial consideration, Australian Courts have construed these claims and made findings as to whether or not such claims are infringed.
Infringement
The issue of infringement is well illustrated in Otsuka Pharmaceutical Co., Ltd v Generic Health Pty Ltd (No 4) [2015] FCA 634 in which the Australian Federal Court considered whether or not the claims of Australian Patent No. 2005201772 were infringed. Relevantly, the claims of this patent included both a Swiss-style use claim and a method of treatment claim. While it was concluded that both the Swiss-style use claim and the method of treatment claim were infringed, the manner in which that conclusion was reached was quite different. I have summarised below how the question of infringement was made out for both claims, and I have provided further detail beneath the summary.
Swiss-style use claim 1
- Direct infringer of claim: Manufacturer of pharmaceutical
- To establish infringement the patentee had to: Show that the claimed medicament is one that has the therapeutic use defined in the claim
- Evidence submitted: Generic Health sought and obtained marketing approval for products in relation to uses covering the uses defined by the claim.
Method of Treatment claim 7
- Direct infringer of claim: Clinician / administerer of drug – need to rely on contributory infringement provisions (s117) to sue manufacturer for indirect infringement of claim
- To establish infringement the patentee had to: Establish that the claimed products were not a “staple commercial product” (as defined in s117), and then that Generic Health had reason to believe that their products would be put to the use defined by the claim.
- Evidence submitted: Extensive evidence from clinicians about the nature of the illness, the course of the illness and the manner of its treatment, including the practice of clinicians in the field.
Swiss-style use claim
In Patent No. 2005201772 Swiss-style use claim 1 was as follows:
Use of a carbostyril compound of [a given structural formula which includes aripiprazole] … or a pharmaceutically acceptable salt or solvate thereof, for the production of a medicament, effective in the treatment of disorders of the central nervous system associated with [the] 5HT receptor subtype, which disorder
(i) is selected from cognitive impairment caused by treatment-resistant schizophrenia, cognitive impairment caused by inveterate schizophrenia, or cognitive impairment caused by chronic schizophrenia, and
(ii) fails to [respond] to antipsychotic drugs selected from chlorpromazine, haloperidol, sulpiride, fluphenazine, perphenazine, thioridazine, pimozide, zotepine, risperidone, olanzapine, quetiapine, or amisulpride.
In deciding that the Swiss-style use claim was infringed, Yates J noted that Generic Health Pty Ltd has sought and obtained marketing approval, and consequently registration of aripiprazole products for treatment of schizophrenia, including maintenance of clinical improvement during continuation therapy. The approvals and registrations encompassed the treatment of all the symptoms and domains of schizophrenia, including the treatment of cognitive impairment associated with schizophrenia in all its forms. The approvals and registrations also encompassed treatment using the aripiprazole products with other drugs or therapies, and use of the products as a first line, second line or later line therapy. Consequently, the therapeutic use of the aripiprazole products, as revealed by the approvals and registrations held by Generic Health Pty Ltd, includes the therapeutic use defined in claim 1.
Yates J stated that when determining infringement of a Swiss-style use claim the 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. It does not matter that the alleged infringer does not actually advertise or promote the medicament specifically for the therapeutic use defined in the claim.
Consequently, Yates J held that Generic Health’s intention to import, market and supply the aripiprazole products, whose scope of therapeutic use, as registered, plainly include the therapeutic use defined in claim 1 would have been a threatened infringement of the claim, had it been valid (the claim was found to lack novelty and an inventive step).
Method of treatment claim
In Patent No. 2005201772 method of treatment claim 7 was as follows:
A method for treating a patient suffering from disorders of the central nervous system associated with [the] 5HT receptor sub-type, which disorder
(i) [is] selected from cognitive impairment caused by treatment-resistant schizophrenia, cognitive impairment caused by inveterate schizophrenia, or cognitive impairment caused by chronic schizophrenia, and
(ii) fails to [respond] to antipsychotic drugs selected from chlorpromazine, haloperidol, sulpiride, fluphenazine, perphenazine, thioridazine, pimozide, zotepine, risperidone, olanzapine, quetiapine, or amisulpride,
comprising administering to said patient a therapeutically effective amount of a carbostyril compound of [the given structural formula which includes aripiprazole] … or a pharmaceutically acceptable salt or solvate thereof.
Unlike a Swiss-style use claim, the direct infringer of a method of treatment claim is the person administering the compound, rather than a company manufacturing the compound. To sue the compound manufacturer for infringement of a method of treatment claim, the patentee needs to rely on Australia’s contributory infringement provisions (section 117 of the Australian Act). Otsuka relied on s117(2)(b) when asserting infringement, which is as follows:
(1) 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.
(2) A reference in subsection (1) to the use of a product by a person is a reference to:
(a) …
(b) if the product is not a staple commercial product—any use of the product, if the supplier had reason to believe that the person would put it to that use; or
(c) …
First, it needed to be established that aripiprazole compounds are not a staple commercial product. Generic Health submitted that aripiprazole is a staple commercial product because it has significant non-infringing uses. Yates J disagreed, stating that Generic Health’s aripiprazole products are only registered and approved for the treatment of schizophrenia, including maintenance of clinical improvement during continuation therapy. It is not conclusive that the aripiprazole products can be put to both infringing and non-infringing uses.
Secondly, it was necessary to establish that Generic Health had reason to believe that the aripiprazole products would be put to the use defined by claim 7. In this regard both parties put forward much evidence, including about the nature of schizophrenia, the course of the illness and the manner of its treatment, including the practice of clinicians in the field. Many experts provided evidence on this point, and Yates J’s discussion of that evidence accounted for a significant portion of the decision. In the end, it was concluded that a not insignificant number of clinicians in Australia would use Generic Health’s aripiprazole products as a realistic and legitimate option to treat a patient’s cognitive impairment associated with schizophrenia, including for the method of treatment claimed in claim 7.
Conclusion
It is advantageous to include both method of treatment and Swiss-style use claims in Australian patent applications, if appropriate. In terms of patentability, method of treatment claims clearly relate to patentable subject matter in Australia, whilst this is less clear for Swiss-style use claims. However, at least in the case discussed above it was much easier to establish infringement of the Swiss-style use claim than for the method of treatment claim.