Using a combination of known elements to create a new invention is an age-old practice to stay ahead in competition. The most convenient combination patent that disrupted the market in 1858 was a pencil with eraser patent owned by Hymen Lipman. There is no statutory bar on combining the known patents to create a new invention. The combination of many elements in mechanical, electrical, and electronic devices is common practice. Combination patents are gaining significance in the drug, chemical, and biotechnology industries as well. We may see biotechnology patents covering combinations of genetic engineering, therapeutic, and biotechnological processes. The surge of patents in inter-disciplinary fields is on the rise. The rules for allowing combination patents are undergoing changes in all the patent jurisdictions. Many commentators ask whether the combination inventions are 'old wine in a new bottle'.

'Combination Inventions' Defined

The combination of a known element 'A' with a known element 'B' for a new use creates a combination invention. The known elements can be patents or otherwise. Most inventions are for improvements and combinations. All improvements and combinations do not pass the muster of being patentable. Earlier, it was simple to get a patent on the combination in many jurisdictions, but now, many statutory and court-proclaimed restrictions are imposed on the patent eligibility of combination inventions.

Combination Invention: Position in the US

The U.S. Supreme Court changed the patent eligibility standard to grant a patent on combination inventions in 2007, when in the KSR v. Teleflex case, the Court ruled that it is not sufficient for the combination invention to pass the Teaching suggestion and motivation test (TSM test) to become patent eligible. This case is a watershed in redefining the obviousness criteria of the patent eligibility of combination inventions. Accordingly, the combination invention must meet the criteria of novelty and inventiveness. The combination should be novel as well as inventive. The invention is considered obvious if there was a prior teaching, suggestion, or motivation in the prior art to combine the elements in the way suggested by the claimed combination. In the KSR case, the combination patent in dispute was for a gas pedal that a driver could adjust based on where the driver was sitting.

Teleflex owned this combination patent. The pedal had an electronic sensor to detect and send its positions to the car's computer. Teleflex alleged that KSR made an adjustable gas pedal with sensor throttle controls for supply to General Motors, which is an infringement of Teleflex's patent. The Supreme Court examined whether an adjustable gas pedal with a sensor was an obvious invention. The U.S. Supreme Court ruled. "the results of ordinary innovation are not the subject of exclusive rights under the patent laws."

The Supreme Court criticised the Federal Circuit's "teaching, suggestion and motivation" test for determining whether a patent is obvious. The Court ruled that an "ordinary innovation" was not patentable. The Court accordingly adopted a more flexible approach, asking whether an improvement is more than a predictable use of prior art elements according to their established functions. The Court observed that a combination patent is the combination, alteration, or unity of elements, techniques, items, or devices where each performed its intended function.

The Supreme Court found Teleflex's adjustable gas pedal was an 'ordinary innovation' and, therefore, such a pedal was not patentable, even if it could pass the TSM test. This approach of the Court appears to be more flexible as asking whether an improvement is more than a predictable use of prior art elements according to their established functions, which is more apt than simply meeting the TSM test.

Position of Combination Inventions in India

The statutory bar on 'combination invention' under the Patents Act 1970 is imposed by the exception of Section 3(d) (new form or combination thereof of known substance ), Section 3(e) (substance obtained by mere admixture) and Section 3(f) (mere arrangement and rearrangement or duplication of known devices). The applicant must meet the certain challenge of Section 3(d), like enhanced efficacy, before such combination is patentable over and above meeting the requirements of novelty and inventive step as stipulated under Section 2(1)(ja). Similarly, the combination invention falling under Section 3(e) must prove the synergistic effect of the claimed combination. For the combination invention falling under Section 3(f), the applicant must prove interaction between the known components/devices, each functioning independently of the other in a known way.

Combination vs Composition

In a recent case, the applicability of Section 3(d) to composition was considered by the Chennai High Court in Novozymes vs Controller. [ (T) CMA (PT) No.33 of 2023]. In this case, the Controller refused the patent for "Phytase Variants with Improved Thermostability" on the ground that the claimed invention is for a known substance which is not patent-eligible under Section 3(d) of the Patents Act, 1970 and that the composition claims (claims 8 to 11) fall within the scope of Section 3(e) because the composition is a substance obtained by the mere admixture of ingredients. On appeal, the Chennai High Court reversed the order of the Controller to grant patent claims from 1-7 as the Court found that the claimed invention of the appellant satisfies the requirement of enhancement of the known efficacy of phytase. It means that section 3(d) does not apply to the composition of known substances.

However, the Court maintained the decision of the Controller on refusal of claims 8 to 11 under section 3 (e ) and observed that:

"On examining the text of Section 3(e) and, indeed, even by placing such text in context, I find that there is nothing therein that limits its application to a composition claim formed by the aggregation of known ingredients. By way of context, I notice that the adjective "known" is used as a qualifier in the following clauses of Section 3: Section 3(d) [known substance"]; Section 3(f) ["known devices"]; and Section 3(p)["known properties of traditionally known component or components"], but is conspicuous by its absence in Section 3(e). I recognise that this view does not accord with that reached by the Intellectual Property Appellate Board in Stempeutics Research Pvt. Ltd. v. Assistant Controller of Patent & Designs, 2020 SCC OnLine IPAB 16, but in the absence of textual or contextual support, I decline to read the adjective "known" into Section 3(e) and place it before the noun "components" therein. The consequence of this conclusion is that, as in this case, if any of the ingredients of the composition independently satisfies the requirements for an invention under the Patents Act, a patent may be applied for and granted in respect thereof, notwithstanding Section 3(e)."

It means the applicability of Section 3 (e) is not linked to the novelty of the components. Even the mere admixture of novel components should depict added effect /synergy for being qualified as patentable subject matter under section 3(e). In this case, the Court found that section 3 (e) is applicable for claims 8-11 as no synergistic effect was shown, and the Controller was right in refusing the grant of these claims. The applicant unsuccessfully argued that section 3(e) is not applicable if the components are novel.

Post-grant Revocation of Combination Patents

It may be noted that in yet another case, the combination patent of Troikaa Pharmaceuticals Indian patent 231479 for Injectable preparations of diclofenac and its acceptable salt was granted by the patent office. However, in the post-grant opposition, the Controller found that the applicant provided no data in the specification to establish or substantiate unexpected synergistic effects between the components used in the formulation when taken individually or in combination. Without going into the history of this case (With multiple pre-grant oppositions) with a subsequent grant (and post-grant opposition), it is sufficient for this discussion to know how the Controller decided to revoke this combination patent falling under section 3 (e). The Controller's decision was based on the premise that

"6. In order to prove that the patented composition is not an admixture, the patent law mandates the Patentee to show that the invention is not an admixture and is primarily compelled to reveal noteworthy synergy between the components used in the preparation of the composition. The composition must not only show any additive effects but exhibit surprising effects that are unexpected results which are not known and must be the surprising result that is called synergistic mixture over the existing knowledge, other than obvious result."

This case is peculiar as the Controller looked for the synergistic effect in post-grant opposition and went on to state that:

"Explicitly, the composition must noticeably show synergistic effect in respect of 'reduction of pain' as the same has claimed to address the problem. However, no data is provided in the specification that proves that there is a reduction in pain at the site of injection. Not a single example is provided in the composition, which could prove there is a reduction in pain while injecting. No clinical data of the claimed formulations is presented in the complete specification to show less pain when an increased therapeutic dose of 75mg in l ml is used over the prior art diclofenac injections."

This rejection may have raised some eyebrows, but it showcased how combination patents may suffer revocation if the synergistic effect is not proved in the specification.

Other 'Combination Inventions' Refused in India

Another combination invention application that the patent office refused at the pre-grant opposition stage was 'A Pharmaceutical Formulation for Paracetamol Injection' filed by Lincoln Pharmaceuticals (1746/MUM/2008). One of the grounds for its refusal was that the combination invention falls under section 3(e). This application was refused by that patent office, stating that "since Glycofurol and alcohol are individually known to solubilise paracetamol, it was imperative to provide comparative data to show the synergistic effect (enhanced solubility) achieved through the combination of solvents." As the applicant did not provide such data in the specification, the opponent succeeded in invoking section 3(e ) limitation on patent eligibility.

Patent granted if synergy is proved in the combination

All is not bad for the combination inventions as the patent office grants many such patents. In cases where the patent is refused by the patent office, an appeal before IPAB was successful. For example, an appeal before IPAB against the refusal of the patent application for a Herbicidal composition (2668/DEL/2015) filed by Willowood Chemicals Private Limited was allowed, and the patent was granted as the appellant was able to show that the description of the patent application explicitly disclosed the data demonstrating the synergistic effect. (OA/53/2020/PT/DEL). The patent office refused this application for want of data supporting the synergistic effect.

Combination drug patent of Sacubitril and Valsartan

In the judgement pronounced by Delhi High in an infringement suit relating to the Indian Patent 229051 for a combination of Valsartan or a pharmaceutically acceptable salt thereof and Sacubitril or a pharmaceutically acceptable salt and a pharmaceutically acceptable carrier owned by Novartis preliminary injunction was allowed. However, in the US, the controversial patent on a drug combination held by Novartis for Entresto (U.S. Pat. No. 8,101,659) for a heart-failure drug combination of Sacubitril and Valsartan was invalidated for different reasons for lacking an adequate written description. The Entresto patent is directed to a combination of two drugs to treat hypertension or heart failure. In particular, the patent claims a combination of valsartan, which is an angiotensin receptor blocker, and sacubitril, which is a neutral endopeptidase inhibitor.

Conclusion

The primary concern of the applicants for the patents for the combination inventions is whether the selected components will pair with each other and produce the added effect. In the US, the TSM test is used to ascertain the patentability of such combination inventions. In India, section 3(e) bars patents on a substance obtained by mere admixture, resulting only in aggregating the properties of the components thereof.

This statutory provision leaves enough room for the grant of patents on the combination invention if the added effect of the components is more than their individual effect. In the Troikaa Pharmaceuticals post-grant opposition case discussed above, even where the Patent Office granted a patent for injectable preparations of diclofenac, the opponent was able to prove that the invention falls under section 3 (e). In this case, the Controller looked for data on the claimed synergistic effect of the combination in the disclosure of invention in the specification. As no clinical data of the synergistic effect of the claimed formulations was found in the complete specification to show less pain when an increased therapeutic dose of 75mg in l ml is used over the prior art diclofenac injections, the patent was revoked by the Controller under section 3 (e).

It is interesting to note that the patent on the combination of Valsartan and Sacubitril [In re: Entresto (Sacubitril/Valsartan) case] passed the TSM test, but the US Supreme Court invalidated this combination patent on the ground of insufficient description. The judicial precedence on the patent eligibility of combination patents has a mixed bag of grants and refusals in all jurisdictions, including India. The common reason in all of the refusals/revocations of combination patents is that the combination, alteration, or unity of elements, techniques, items, or devices was of the kind where each of the elements performed its intended function. There was no synergistic effect in the invented combination.

In the case where synergy was claimed, it was not supported by the comparative data in the description. The combination inventions are patentable in India if the applicant proves the combination produces an added effect. The combination inventions are not 'old wine in new bottle', but rather patent-eligible 'new inventions in old bottles' if comparative data in the patent description support the added effect of the combination. Expert advice on drafting such applications would save the patent from being revoked even after the grant.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.