New Use of a Known Substance

1The Patents Act requires novelty per se. It does not allow for novelty of use. The Patents Act does not contain any provision which allows for novelty of use. This is a distinguishing feature of the Patents Act which has remained the same over the years, where as countries like UK have relaxed the novelty requirement to allow novelty of use.

2There has been a move towards relaxing the novelty standard for pharmaceuticals. In the recent years, the pharmaceutical industry has witnessed a marked reduction in the possibility of discovering new things. This shifted the focus of research to the discovery of new uses or purposes of old substances in old ways. Patent law traditionally refused to recognise the discovery of a new advantage of an old thing used in an old way as being novel. (Ibid, pp 426-27.) This was because patent law recognised the particular use of a product as a part of a claim for the product itself." (Patents Act 1970, s 48.) The rights of a patentee includes the right of using the product. The product would thus lack novelty even if it was previously employed to a different use. (Adhesive Dry Mounting Co Ltd v Trapp & Co (1910) 27 RPC 341.)

3An issue then arises whether the new use of a known substance is patentable under art 27(1) of the TRIPS Agreement. This forms a part of the larger issue of the standard of novelty prescribed by the TRIPS. The TRIPS Agreement requires the novelty of product or of process for which a patent is claimed. It requires the product or the process to be new. In other words, the TRIPS Agreement mandates novelty per se. It may be argued that since patents for new uses of known substances are drafted in the form of a process claim (Swiss claim), it would come under the ambit of a new process, within the existing mandate of TRIPS. But there is no express provision conferring novelty of use akin to the provisions found in the EPC and the UK Patents Act. (See European Patent Convention 1973, art 52(4); UK Patents Act 1977, s 2(6).) The TRIPS is silent about novelty of purpose or use. The silences within the TRIPS further reiterate the proposition that the TRIPS is a minimum-standard setting agreement. The novelty standard set by the TRIPS Agreement is aptly summarised in the words of one of the TRIPS negotiators for India: (Jayashree Watal, Intellectual Property Rights in the WTO and Developing Countries, OUP, 2001, p 104.)

The TRIPS Agreement is silent about the patentability of new uses of known substances, including second or subsequent therapeutic uses for known pharmaceutical products, eg aspirin for heart ailments or AZT, an anti-cancer drug with a new and more widely accepted use for treating HIV/AIDS. Most patent laws that allow this, have a separate provision for it. It is not as if TRIPS negotiators were not aware of this controversy. This subject was discussed in the context of Article 39.3 on test data, where it was decided not to include such new uses (see Chapter VI). The language of Article 27.1 refers only to the patentability of ‘products or processes’ and not of uses. Novelty is not defined to include new uses of known substances unlike in some pre-TRIPS patent laws that specifically included this provision. (For instance, the EPC in art 54 on novelty includes a clause that prohibits exclusion from patentability of any use in a medical method of any known substance, provided such use is novel. Article 7c of the Swiss Patent Act 1976 recognises as novel, new uses of known substances for the implementation of methods of treatment or of diagnosis.)

Moreover, a new therapeutic use of a known medicine would also not meet the criterion of industrial applicability. Indeed, second or subsequent use claims can be treated as a method of treatment, which even if otherwise patentable, can be excluded under TRIPS. Even though the TRIPS text does not specify any exception to new uses of known substances, it can be concluded that TRIPS does not require the grant of such patents [Emphasis supplied].

4India continues to follow the traditional position of not allowing new uses for known substances. The second part of s 3(d) comprehensively prohibits patents for new uses of known substances. In enacting the second part of s 3(d), the Patents Act has embodied an age-old principle of not recognising novelty of use or purpose. Novelty, in the manner in which the concept is understood under the Patents Act and the TRIPS Agreement, is confined to novel products and processes. It does not envisage novelty of use or purpose of an already known substance. It would be illogical to grant new patents for already known substances as the earlier grant will cover all forms of uses and purposes to which the invention can be applied. (See Patents Act 1970, s 48 which enumerates the rights of a patentee to include the use of a product.) Moreover, to relax the standard of novelty for pharmaceuticals alone may violate the general mandate in art 27.1 that patents shall be available for any inventions in all fields of technology.

5Some countries have made an exception to the general rule of novelty by making legislative provisions for recognising novelty of use largely to appease the interests of the pharmaceutical industry. (See Lionel Bently and Brad Sherman, Intellectual Property Law, OUP, 2000, p 427.) The United Kingdom relaxed the general rule on novelty to accommodate new medical uses. (See UK Patents Act 1977, s 4(2).) The EPC also provides for a similar provision. (See European Patent Convention 1973, art 52(4).) In the United Kingdom, the relevant provision provided only for first medical use. But following the trend set by the EPO, the UK courts have interpreted the above provision to include second and subsequent medical uses. (See Lionel Bently and Brad Sherman, Intellectual Property Law, OUP, 2000, p 427.)

6In the light of the long-standing principle on how novelty is understood, novelty of use cannot be implied in the absence of an express legislative provision allowing for the same. This would be more so if the patent legislation of a country has the standard exception on methods of treatment as contained in the Patents Act and the UK Patents Act. (See Patents Act 1970, s 3(i); UK Patents Act 1977, s 4(2).) “Section 4(2) of the UK Patents Act bars patents for method of treatment. It reads:

4. Industrial application.— … (2) An invention of a method of treatment of the human or animal body by surgery or therapy or of diagnosis practised on the human or animal body shall not be taken to be capable of industrial application.

7To overcome the bar imposed by s 4(2) of the UK Patents Act, s 2(6) was introduced which reads:

2. Novelty.- … (6) In the case of an invention consisting of a substance or composition for use in a method of treatment of the human or animal body by surgery or therapy or of diagnosis practised on the human or animal body, the fact that the substance or composition forms part of the state of the art shall not prevent the invention from being taken to be new if the use of the substance or composition in any such method does not form part of the state of the art.

8Section 2(6) of the UK Patents Act confers novelty through a new use even if the substance or composition formed a part of the state of the art. The above provision allowed for patents for the discovery of first medical use. When the issue arose whether the above provision would cover second and subsequent medical uses of a known substance, the UK courts have, following the decision of the EPO in Eisai/Second Medical Indication case, held that second medical uses will be patentable if they are drafted in the style of a Swiss claim. (G5/83 Eisai/Second Medical Indication [1985] OJ EPO 64.) (See Wyeth’s Application (1985) RPC 545; Bristol-Myers Squibb v Baker Norton Pharmaceuticals (2001) RPC 1, pp 18, 24-6; Monsanto v Merck (2000) RPC 77, p 92 (CA); Pharmaceutical Management Agency v Commr of Patents (1999) RPC 752 (HC)(NZ).)

9A ‘Swiss’ form of claim (‘Swiss claim’) is a claim to the use of a known pharmaceutically active compound for the manufacture of pharmaceutical compositions in which the compound exhibits previously unknown therapeutic activity. The claim is so drafted so as to cover the discovery of a subsequent medical use of a known substance. The commonly cited example involves the well-known analgesic ‘aspirin’. Aspirin was introduced as a pain-killer but somewhere down the line, research established that aspirin had blood-thinning properties which could be used for preventing blood clots, and thereby reducing the incidence of stroke. The law in UK will allow for a patent for the second medical use of aspirin, ie, the use of aspirin in preventing blood clots, if the same is worded in the form of a Swiss claim. The United Kingdom initially disallowed Swiss claims, but later allowed them to align its patent law with the EPC. Two illustrations of a Swiss claim are shown below:

The use of a substance ‘x’ for the manufacture of medicine ‘y’ for the treatment of disease ‘z’. The use, in the manufacture of a medicament, of [the active compound] as an active ingredient in a [the newly invented activity] composition in admixture with an inert carrier.

10A Swiss form of claim is in effect a claim for a process. Section 3(d) of the Patents Act does not allow patents for any new property or new use for a known substance. Even in the absence of s 3(d), Swiss claims will not be allowed under s 3(i) of the Patents Act. (See John Wyeth & Brother Ltd’s Application (1985) RPC 545, p 563.) If patents in the form of a Swiss claim were to be granted, they will stand the risk of being revoked under s 64(1)(l) if the invention was used earlier in India.