High Court decides important issues relating to patentability of methods of medical treatment, and contributory infringement of pharmaceutical patents

Further to our earlier “Breaking News” post, the High Court has handed down a much anticipated decision in Apotex v Sanofi-Aventis. The decision is important because it definitely determines that methods of medical treatment of human beings are patentable subject matter within the meaning of s18(1) of the Patents Act 1990 (Cth). Further, in circumstances where a pharmaceutical product has more than one use, one which infringes and one which does not infringe a valid patent, the High Court’s decision makes it clear that supply of the product with instructions that it is only to be used for the non-infringing use, will not infringe.

Sanofi’s Patent and Apotex’s Product

The proceedings related to Sanofi’s patent which claimed a “method of preventing or treating … psoriasis, which comprises administering to a recipient an effective amount of” leflunomide. Sanofi was also the patentee of an expired patent relating to the preparation and composition of leflunomide.

Apotex obtained registration on the Australian Register of Therapeutic Goods of a product containing leflunomide that was indicated (that is, approved) for use in the treatment of rheumatoid arthritis (RA) and psoriatic arthritis (PA), but specifically not indicated for the treatment of psoriasis that is not associated with manifestations of arthritic disease.

Sanofi’s case was that Apotex intended to supply its leflunomide product for the treatment of PA and that use of the product in the treatment of PA would infringe Sanofi’s patent because it would in fact treat psoriasis. Sanofi argued that such use (that is, in the treatment of psoriasis) was in accordance with instructions for use of the products provided by Apotex, and reasonably expected by Apotex for the purpose of s117 of the Patents Act.

Contributory infringement under s117

s117 of the Patents Act provides that if use of a product would infringe a patent, then supply of that product is an infringement. A reference in this context to ‘use’ is a reference to:

a) if the product is capable of only one reasonable use, that use; or

b) if the product is not a staple commercial product, any use of the product that the supplier had reason to believe the person would put it to; or

c) in any case, use of the product in accordance with any instructions or inducement given to the person by the supplier, or contained in an advertisement published by or with the authority of the supplier.

It was common ground that almost every person with PA has or will develop psoriasis, that patients who suffer from psoriasis will usually be referred to a dermatologist for treatment and that leflunomide is not prescribed in Australia to treat psoriasis alone. It was also common ground that leflunomide is used by rheumatologists to treat RA and PA, and when leflunomide is prescribed to treat a patient with PA, it is expected to also prevent or treat the patient’s psoriasis.

At first instance, Jagot J found that Apotex’s leflunomide product would infringe Sanofi’s patent under s117(2)(b) because Apotex had reason to believe that the person to whom the product is supplied would put the product to use in the treatment of psoriasis. This was in part because her Honour found that almost all people who are treated with leflunomide for PA would in fact also be treated for psoriasis. Jagot J also found that Apotex infringed under s117(2)(c) because the product information instructed rheumatologists to use the product in the treatment of psoriasis.

On appeal, the Full Court found that Jagot J’s construction failed to recognise that the claim of the patent was to a method of treating a specific human ailment following a deliberate exercise of diagnosis and prescription, and that the claimed method of treatment is only utilised by the deliberate administration of leflunomide to prevent or treat psoriasis, not where it is administered with some other objective (ie treating arthritis) in circumstances where it happens to achieve the result of preventing or treating psoriasis as an unsought consequence. However, the Full Court did not disturb Jagot J’s finding that sale of the product would infringe under s117(2)(b) on the basis that Apotex had reason to believe its product would be used to treat psoriasis, and under s117(2)(c) on the basis that Apotex’s product information amounted to an instruction to use the product to treat psoriasis.

The High Court however, noted that the under the Therapeutic Goods Act, a product is only registered for specific therapeutic uses. In the case of Apotex’s leflunomide product, the indication in the product information amounted to an “emphatic instruction” to restrict its use to uses other than use in accordance with the claimed invention. The High Court found that the product information did not instruct recipients to use the product in accordance with the patented method. As such, s117(2)(c) was not engaged. Similarly, in light of the restricted indication, the Court found that “it was not shown, nor could it be inferred, that Apotex had reason to believe that the unpatented pharmaceutical substance … would be used by recipients in accordance with the patented method, contrary to the indications in Apotex’s approved product information document.”

The important effect of this aspect of the decision is that a supplier of a pharmaceutical product which has more than one potential use will not be found to infringe where the product indication specifically excludes the patented use.

Validity of patents relating to methods of medical treatment

As noted by French CJ, the primary question to be decided by the High Court was whether methods of medical treatment of human beings are patentable subject matter in Australia. Hayne J dissenting, each of French CJ, Gageler J and Crennan and Kiefel JJ decided that methods of treatment are patentable inventions under the Patents Act.

The Court carefully examined the legislative history of the requirement in s18 of the Patents Act that a patentable invention be a “manner of manufacture within the meaning of section 6 of the Statute of Monopolies” (enacted in 1623!). This requirement was adopted in UK patents legislation which formed the basis of the 1903 and 1952 Australian Acts. The requirement was abandoned in the 1977 UK Patents Act, which specifically provided that methods of treatment of the human body were excluded from patentability. This brought the UK position in line with the European Patent Convention.

In Australia, the requirement that an invention be a “new manner of manufacture within the meaning of s6 of the Statute of Monopolies” was retained when the 1952 Act was repealed and the 1990 Act enacted because it was thought that the “manner of manufacture” criterion for patentability ought to continue to be applied on a case by case basis rather than codifying patentable and non-patentable subject matter.

The High Court noted that in both the UK and Australia, for many years, it was generally accepted that methods of treatment of the human body were not patentable subject matter. However, in Rescare Ltd v Anaesthetic Supplies Pty Ltd (1992) 111 ALR 205, the Full Court of the Federal Court, following New Zealand jurisprudence, found that there was no basis for the proposition that a method of therapeutic treatment is not patentable.

ResCare was followed in subsequent Australian decisions, however in New Zealand, an exclusion of methods of medical treatment of human beings from patentability remains. Similarly, in the United Kingdom and Europe, there is a general exclusion of methods of treatment or diagnosis from patentability (which does not apply to “a substance or composition for use in an excluded method”). In the United States, there is no categorical exclusion on methods of treatment from patentability, provided the invention does not relate to a law of nature, physical phenomenon or abstract idea (for more on the US position, see our post relating to Association for Molecular Pathology v Myriad Genetics Inc here). There is also a bar to actions for patent infringement against medical practitioners in the United States for “the performance of a medical or surgical procedure on a body”. In Canada, while there is no express exclusion from patentability of methods of medical treatment of the human body, the Supreme Court of Canada has held that such methods are not patentable (but a novel use of a known compound is patentable subject matter).

In this case, French CJ noted that there are competing interests between granting monopolies to encourage technical innovation, and ensuring unconstrained access by medical practitioners and their patients to new medical methods and processes. However, the Court noted that an absence of an express exclusion on methods of treatment from patentability by Australian Courts should not support a conclusion that the legislature did not intend such an exclusion, and that the question needed to be answered by an analysis of the case-by-case development of principle. Here, French CJ found that excluding methods of medical treatment from patentability represented an anomaly without clear and consistent foundation, and noted that:

“the rubric “manner of new manufacture” in a logically and normatively coherent way is not served by excluding from its scope methods of medical treatment of human beings. Methods of medical treatment can fall within the scope of a manner of new manufacture within the meaning of s 6 of the Statute and therefore within s 18(1)(a) of the 1990 Act. Nor, on the reasoning which supports that conclusion, does “general inconvenience” (upon which, in any event, Apotex placed no reliance) appear to provide any basis for their exclusion.”

Similarly, Crennan and Kiefel JJ, with whom Gageler J agreed, found that assuming all other requirements for patentability are met, a method (or process) for medical treatment of the human body which is capable of satisfying the test in National Research Development Corp v Commissioner of Patents (1959) 102 CLR 252, namely, that it is a contribution to a useful art having economic utility, can be a manner of manufacture and patentable within the meaning of s18 of the Patents Act.

Interestingly, while it was not necessary for the High Court to consider activities or procedures of doctors when physically treating patients, the Court did note that a logical distinction may exist between methods of medical treatment and activities of doctors, noting that the procedures of doctors when treating patients may be “essentially non-economic” so as not to satisfy the NRDC test for patentability, “because they are not capable of being practically applied in commerce or industry, a necessary prerequisite of a “manner of manufacture”.

The High Court’s confirmation that methods of treatment may amount to a manner of manufacture within the meaning of s18 resolves the question of the patentability of these inventions.