Draft Trans-Pacific Partnership Treaty – Patentability of Methods of Medical Treatment

The leaked draft TPP treaty has a number of provisions concerning medically related claims. My last posts dealt with second medical use claims, and a prohibition on any requirement of enhanced efficacy for pharmaceuticals. This post deals with methods of medical treatment, addressed in Art E.1(3)(b). I find the notation in this provision to be a bit confusing, but as I understand it, the position of the parties is as follows:

US proposes that:

3. Each Party shall make patents available for inventions for (b) diagnostic, therapeutic, and surgical methods for the treatment of humans or animals if they cover a method of using a machine, manufacture, or composition of matter

Others (including Canada, but excluding Japan) propose:

3. Each Party may exclude from patentability (b) diagnostic, therapeutic, and surgical methods for the treatment of humans or animals.

The majority position reflects in TRIPS Art 27(3)(a); and see also EPO Art 53(c). The basic question is whether this potential exclusion of methods of medical treatment should be maintained, or eliminated.

Japan opposes any provision, one way or the other, on this issue.

In Canadian law, the FC/FCA has held that methods of medical treatment are not patentable, so the Canadian negotiating position is consistent with current law. However, once we go below the surface, current Canadian law on this point is a nightmare of conflicting case-law. The problem is that the most obvious “therapeutic method for the treatment of humans” is to administer a pharmaceutical, but if we know anything about the patent system, it is that patents are essential to pharmaceutical innovation. If the pharmaceutical is subject to a compound claim, then a prohibition on patenting therapeutic methods is not formally engaged, but it nonetheless raises the question of why methods of medical treatment should be prohibited, if the most common form of medical treatment is effectively patentable? And once we slide over into related inventions such as second medical use claims, or dosage regimes, this question begins to bite in practice. The attempt to resolve this conflict has led to the current confusion in the case law, and not just in Canada.

The most general argument against patenting of methods of medical treatment, at least as narrowly defined, is that innovations in surgical techniques, for example, are not subject to the same incentive structure as pharmaceutical inventions. It may be that the incentive to hone one’s skill in order to become known as a leading surgeon provides enough of an incentive to innovate, though if expensive clinical trials are necessary, this argument becomes weaker. Two other arguments are commonly made, namely (a) physicians should be able to give their patients the treatment which they feel is medically best without fear of a patent infringement action; and (b) some methods of medical treatment, such as surgical methods, may turn on the exercise of skill that cannot be defined sufficiently precisely to be subject to a clear claim. I find these arguments less persuasive, as these problems are arguably better addressed with specific provisions addressed at the problem itself, such as the US defence for physicians set out in 35 USC § 287(c)(1). Claims to ill-defined applications of skill are presumably unpatentable in any event as being ambiguous.

It is important to note that the US does not simply propose that methods of medical treatment should be patentable as such, but only “if they cover a method of using a machine, manufacture, or composition of matter.” This may be an attempt to address the problem of claims to poorly defined exercises of skill, by tying the claim to a tangible item rather than skill alone. (It does not address the problem of physicians be liable for using such devices, but presumably members would be free to implement a US-style defence; and as a practical matter, it should be easy for a surgeon to avoid this problem by using a authorized and licenced device.) 

But this provisio to the US proposal would also have the effect of entrenching the extremely problematic decision of the USSC in Mayo v Prometheus, which held that diagnostic correlations central to personalized medicine are unpatentable as such. It may well be that entrenching Prometheus is the US’s motivation for adding this phrase. Either way, this proviso is very troubling. In my view, Prometheus was probably wrongly decided, and it is unquestionably extremely controversial. In its decision, the USSC itself admitted that it had no idea as to whether its holding was sound from an innovation perspecitve (slip op 22-24). It consequently based its decision on precedent, right or wrong, rather than policy:

In consequence [of the uncertainty as to the impact on innovation], we must hesitate before departing from established general legal rules. . . .We need not determine here whether, from a policy perspective, increased protection for discoveries of diagnostic laws of nature is desirable.

The US government, in contrast, cannot shift the responsibility to another body. It must base its decision on policy considerations, difficult as that may be. As the USSC said, “we must recognize the role of Congress in crafting more finely tailored rules where necessary.” I am astonished that the US government has chosen to try to entrench a USSC decision which is very controversial and very problematic, and which was explicitly not based on sound policy considerations. I am tempted to think that the US is proposing this proviso only so that the TPP treaty will not require it to make changes to its own Patent Act. If that is so – and I hope it is not – it would hypocritical, as the US would be asking other countries to improve their patent legislation, without being willing to put its own house in order. And while the US proposal would not require members to follow Prometheus, that would certainly be the obvious thing to do. If the US is successful in this proposal, I anticipate that in a few years, after the US has fixed Prometheus in its own law, there will be another round of trade treaty negotiations in which the US will insist that member countries remove the proviso “if they cover a method of using a machine, manufacture, or composition of matter,” which it is now insisting upon.

On the whole, I am inclined to think that it is over-reaching to try to settle this issue in these treaty negotiations. Perhaps Japan has the best position on this provision.