7 November, 2017
INTRODUCTION
A recent 5-judge Singapore Court of Appeal (“CA”) decision has provided food for thought on the sufficiency of purpose-limited product claims for second and subsequent uses of a known substance or composition under section 14(7) of the Patents Act (“PA”) without having to resort to Swiss-style claims. In Warner-Lambert Company LLC v Novartis (Singapore) Pte Ltd [2017] SGCA 45, Warner-Lambert Company LLC (“WLC”) appealed against the High Court’s (“HC”) dismissal of their application to amend their patent from a method of treatment claim to a Swiss-style claim. At issue was whether the HC Judge had exercised his discretion correctly in disallowing the proposed amendments. The CA also took the opportunity to make observations
on 2 novel issues:1
(a) whether the PA protected subsequent medical uses of known substances; and
(b) whether Swiss-style claims were valid under the Patents Act.
BRIEF FACTS
WLC was the owner of a patent which claimed a monopoly over the use of pregabalin for the treatment of pain (the “Patent”). Pregabalin was manufactured and distributed by WLC under the product “Lyrica” in Singapore.2
In 2015, Novartis (Singapore) Pte Ltd (“Novartis”) applied to the Health Sciences Authority for product licences in respect of pregabalin products. Pursuant to section 12A(3)(a) of the Medicines Act, Novartis notified WLC that the Patent would not be infringed by the doing of the acts for which the product licences were sought.3
WLC disagreed and commenced an action against Novartis to stop Novartis from obtaining such licences. In particular, WLC sought a court declaration that the doing of the acts for which the product licences were sought would infringe its Patent.4
However, Novartis contended that WLC’s Patent had claimed a monopoly over methods of treatment of the human body. This was prohibited by section 16(2) of the PA which provided that methods of treatment of the human body were not to be taken to be capable of industrial application. WLC thus sought to amend their method of treatment claim to a Swiss-style claim which takes the following generalised form:5
“the use of compound X (i.e. pregabalin) in the manufacture of a medicament (i.e. Lyrica) for a specified (and new) therapeutic use Y (i.e. treatment of pain)”
The validity of Swiss-style claims had not been considered by the Singapore Courts before. However, such claims are accepted by the Patent Registry of the Intellectual Property Office of Singapore(“IPOS”).
The CA affirmed the HC Judge’s decision to disallow WLC’s amendments on the grounds that:6
(a) there was unreasonable delay by WLC in seeking the proposed amendments; and
(b) the proposed amendment of the method of treatment claim to a Swiss-style claim extended the protection conferred by the patent as granted.
Finally, the CA made some important observations on Swiss-style claims which may affect the development of patent law, the Examination Guidelines for Patent Applications at IPOS (April 2017 version) (the “Examination Guidelines”) and patentees who own patents with Swiss-style claims.
UNREASONABLE DELAY BY WLC IN SEEKING AMENDMENTS
The CA found that WLC had delayed in seeking amendments and there were no reasonable explanations for the delay.7
First, WLC had delayed for more than a decade before applying to amend the Patent. The clock ran when WLC had constructive
knowledge of the Patent’s potential invalidity.8
As early as 4 May 1998, WLC obtained an International Preliminary Examination Report (“IPER”) which stated that method of treatment claims may be inadmissible in some patent systems. However, the application to amend the Patent was only made on 26 August 2015.9
Further, as an established pharmaceutical company with a sizeable patent portfolio, WLC should have known of the prohibition against method of treatment claims.10
Indeed in 2005, 2007, and 2008, WLC had successfully applied to amend 3 of its Singapore patents (pre-grant) from method of treatment claims to Swiss-style claims.11
Second, there were strong public policy considerations that the burden to ensure a patent’s validity rests on the patentee and not the public.11
Ensuring the timeliness of patent amendments upholds the public interest in preventing unworthy inventions from monopolising the market. The CA stressed that a lenient approach should not be adopted as it would encourage dilatory conduct and wilful blindness on the part of patentees, and cause invalid patents and unworthy inventions to monopolise the market for longer than necessary.13
EXTENSION OF PATENT PROTECTION AS GRANTED BY THE PROPOSED AMENDMENTS
The CA found that the Patent was obviously and totally invalid as it was concerned with method of treatment claims. It was therefore artificial to even consider whether amendments would extend the protection conferred by the Patent.14
This was because an invalid patent conferred no protection and to allow the amendment would be to validate what was invalid from the beginning. This strict approach was justified on the basis that the patentee was responsible for ensuring compliance with
the requirements in the Patents Act under the self-assessment system.15
Nonetheless and for completeness, the CA held that an amendment of method of treatment claims to Swiss-style claims would extend the protection conferred by the Patent as granted. This was because the granted claims protected the use of the compound for a specific purpose (i.e. method of treatment claims), and not the manufacture of the medicament (i.e. Swiss-style claims), both of which are mutually exclusive.16
COMMENTS ON THE VALIDITY AND NECESSITY OF SWISS-STYLE CLAIMS
The CA acknowledged that Swiss-style claims were conceived to afford patent protection to subsequent medical uses of a substance by steering clear of the twin perils of the statutory preclusion of methods of treatment and the lack of novelty of subsequent medical uses.17
One, the making of a substance for treatment is different from the treatment itself. Two, the subsequent (new) medical use confers novelty on the method of manufacture.18
Thus, the novelty lies in the making of the substance, and not the subsequent medical use. Both the HC and the CA observed that this manner of conferring novelty on the method of manufacture was “fiction[al]”.19
The CA went so far as to describe this as a questionable way of getting around the peril of the lack of novelty (of subsequent medical uses).20
To avoid this struggle, the CA pointed out that the peril of the lack of novelty (of subsequent medical uses) might not even exist at all. In fact, an ordinary and purposive interpretation of section 14(7) of the PA would be that this section protects and confers novelty on subsequent medical uses of a known substance or composition. Section 14(7) of the PA essentially provides that the fact that a substance or composition forms part of the state of the art shall not prevent an invention from being taken to be new if the use of the substance or composition in any method of treatment of the human or animal body by surgery or therapy or of diagnosis practised on the human or animal body does not form part of the state of the art. The CA remarked that finding a new use of a known substance was no less novel and innovative than finding the substance itself.21
Therefore, purpose-limited product claims might be sufficient to protect subsequent medical uses of a substance and Swiss- style claims might not be necessary at all.22
IMPLICATIONS AND CONCLUSION
This case provides guidance to patentees on the extent they are allowed to amend their patents to overcome lack of novelty in their inventions:
(a) the burden lies on them to ensure their inventions comply with the patentability requirements under the PA, especially if their patents had been granted during the self-assessment system (i.e. before 14 February 2014);
(b) amendments to obviously invalid patents will be disallowed;
(c) amendments should be made expeditiously when patentees have constructive knowledge of an invention’s possible invalidity (whether arising from search and examination reports, or from oppositions/ objections to international applications, or possible revocations of international patents); and
(d) amendments of method of treatment claims to Swiss-style claims will be disallowed as it extends the scope of patent protection.
However, such amendments may not be necessary given that purpose-limited product claims may be allowed under the PA.
Further, this case may have important implications on the IPOS’ Examination Guidelines. One possible scenario is that the Examination Guidelines could be revised to specifically allow purpose-limited product claims and do away with Swiss-style claims. Existing patents and pending patent applications with Swiss-style claims may be required to be amended to the new claim formulation or be objected to as lacking clarity.
While the CA sees no reason to disagree with the validity of Swiss-style claims at this stage, patent owners should keep themselves updated on any changes to the Examination Guidelines and act accordingly. A failure to act expeditiously may lead to a finding of undue delay.
Lastly, this case may be a precursor for interesting developments in patent law.
Allowing purpose-limited product claims may lead to possible restrictions on the freedom of medical practitioners to prescribe or administer generics (which are made for a known purpose) for the new medical use. Further, it is unclear how a purpose-limited product claim will affect ‘dosage regime’ claims (i.e. where a higher or lower dosage will be more effective in treating the same disease) or ‘new patient group’ claims.
Much remains to be seen how the law can strike a balance between giving the patentee a proper reward for his contribution to the art by elucidating the new use for the drug, and not excluding the competing manufacturer from making the drug for its known purpose. This may arguably lie in the province of the Legislature and not the Courts.
1 Warner-Lambert Company LLC v Novartis (Singapore) Pte Ltd [2017] SGCA 45 (“Warner-Lambert (CA)”) at [6].
2 Ibid, at [1].
3 Ibid, at [2].
4 Ibid.
5 Ibid, at [80].
6Ibid, at [97].
7Ibid, at [40].
8 Ibid, at [48].
9 Ibid, at [13] and [14].
10 Ibid, at [57].
11 Warner-Lambert Co LLC v Novartis (Singapore) Pte Ltd [2016] SGHC 106 (“Warner-Lambert (HC)”) at [97].
12 Warner-Lambert (CA) at [63].
13 Ibid, at [48] and [49].
14 Ibid, at [62].
15 Ibid, at [63].
16 Ibid, at [74] – [76].
17 Ibid, at [80] and [85].
18Warner-Lambert (HC), at [40].
19Warner-Lambert (CA), at [88] and Warner-Lambert (HC) at [40].
20 Warner-Lambert (CA) at [96].
21Ibid, at [82] – [88].
22 Ibid, at [89]
