Bayer Intellectual Property GMBH and Others v Dr Reddy's Laboratories (Pty) Ltd

• Jurisdiction: South Africa
• Judge: Keightley J
• Judgment Date: 15 December 2021
• Docket Number: 2007/06238-5
• Hearing Date: 26 August 2021
• Court: Commissioner of Patents
• Citation: 2022 JDR 0071 (CP)

Keightley J:

INTRODUCTION:

1.

This is an application for an interim interdict restraining the respondent from infringing the claim of a South African patent by using, disposing of or offering to dispose of the anticoagulant medicament, Rivaxored in, or importing it into, the Republic, pending the final determination of a patent infringement action which has been instituted simultaneously by the applicants. The patent in question is South African Patent No. 2007/06238 (the patent or patent-in-suit): "Prevention and Treatment of Thromboembolic Disorders." It relates to the manufacture of tablets marketed as Xarelto and iXarola, in which the active ingredient is rivaroxaban.

2.

The applicants all form part of the corporate Bayer group of companies. The first applicant, Bayer Intellectual Property GmbH, is the registered proprietor of the patent-in-suit, and the second and third applicants are registered licensees under it. For simplicity, I refer to the applicants collectively as Bayer.

3.

The respondent is Dr Reddy's Laboratories (Pty) Ltd (Dr Reddy's), which is a company incorporated in South Africa. It is a wholly owned subsidiary of Dr Reddy's Laboratories Limited, which is a multinational pharmaceutical company located in Hyderabad, India. Dr Reddy's is a generic medicine supplier. It is common cause that Dr Reddy's launched its generic product, Rivaxored, which it imports from India, in South Africa on 31 March 2021. Bayer contends that this is an infringement of the patent-in-suit.

4.

In the infringement action Bayer seeks a final interdict for the remaining life of the patent-in-suit, as well as damages. There is also ancillary litigation between the parties. On 1 April 2021, shortly prior to launching Rivaxored in South Africa, Dr Reddy's instituted an application to revoke Bayer's patent. Bayer filed its counter

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statement in that application, whereafter Dr Reddy's applied twice to amend its statement of particulars. As matters stood at the time the present application was heard Dr Reddy's founding evidence in its revocation application had not yet been filed. Dr Reddy's has also filed a counterclaim in the infringement action in which they seek to set aside an amendment to the patent specification that was applied for and granted in August 2020 (the post-grant patent amendment).

5.

It can safely be said that the present application is but the first step in what will no doubt be extensive further litigation between the parties. However, it is important to bear in mind that in these proceedings I am concerned only with the application by Bayer for interim relief, and any findings I make on the broader issues in dispute will be on a prima facie basis.

TEST FOR INTERIM RELIEF:

6

In order to succeed in an application for an interim interdict, an applicant must establish a prima face right, though open to some doubt. It must satisfy the court that there is a well-grounded apprehension of irreparable harm if the interim relief is not granted and it ultimately succeeds in establishing its right. The balance of convenience must favour the applicant, and the applicant must have no other satisfactory remedy. [1]

7.

The test to be applied for purposes of determining whether, on the facts, the applicant has met these requirements is well established.

"The proper manner of approach I consider is to take the facts as set out by the applicant, together with any facts set out by the respondent which the applicant cannot dispute, and to consider whether, having regard to the inherent probabilities, the applicant could on those facts obtain relief at trial. The facts set up in contradiction by the respondent should then be considered. It serious doubt is thrown on the case of the applicant he could not succeed in

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obtaining temporary relief, for his right, prima facie established, many only be open to some doubt. But if there is mere contradiction, or an unconvincing explanation, the matter should be left to trial and the right be protected in the meanwhile, subject of course to the respective prejudice in the grant or refusal of interim relief." [2]

8.

This test was endorsed in Gool, [3] subject to the clarification that the question is whether the applicant "should", not "could", on the applicant's admitted facts obtain final relief at trial. In patent matters, where an interim interdict is sought, courts should refrain from making final findings, but nevertheless consider the relative strength of each party's case. Each case must be decided on a basis of fairness, justice and common sense I relation to the whole of the issues [4]

9.

Although other issues are placed in dispute, much of the present case turns on whether Bayer has established a prima facie right under the patent. Dr Reddy's disputes that it has done so. It relies on its revocation application in which it has asserted that the invention claimed by Bayer under the patent is not patentable "in that the invention claimed does involve an inventive step having regard to the matter made available to the public immediately prior to the priority date". As I discuss shortly, the claim in the patent is in what is commonly referred to as the Swiss form. Dr Reddy's also contends that claims in this form are not permissible under South African law, alternatively, that the patent-in-suit is not a genuine Swiss form claim. It accepts that to succeed in its defence in the application it must place serious doubt on the validity of the patent.

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THE PATENT-IN-SUIT

10.

The patent-in-suit was filed in South Africa on 27 July 2007 as a national phase entry into South Africa from a Patent Co-Operation Treaty international application (PCT/EP2006/000431). It was granted on 26 November 2008. Its earliest priority date is 31 January 2005. The post-grant amendment of the patent was filed on 19 March 2020 and allowed on 3 August 2020. It is common cause that the patent-in- suit is in force and is due to expire on 19 January 2026. A copy of the complete specification and the register sheet of the patent is attached to the founding affidavit.

11.

There is a single claim in the patent-in-suit demarcating the monopoly Bayer stakes out for itself. It is stated in the following terms:

"The use of the compound (rivaroxaban) for the manufacture of a medicament in an oral dosage form for the treatment of a thromboembolic disorders for administration no more than once daily for at least five consecutive days, where said compound has a plasma concentration half life of 10 hours or less when orally administered to a human patient, wherein the thromboembolic disorder is pulmonary embolism, deep vein thromboses or stroke, and wherein the oral dosage from is a rapid-release tablet." (My emphasis)

12.

Based on its claim, Bayer contends that the patent confers on it the exclusive right to manufacture oral, rapid-release rivaroxaban tablets which are to be taken no more than once a day for at least five days for use in the treatment of the identified thromboembolic disorders.

13.

It is common cause that the underlined portion of the claim identifies that the claim is worded in the Swiss form. It is also common cause that until recently a separate patent held by Bayer was in force in respect of the compound, rivaroxaban. I refer to this as the compound patent. It expired in December 2020 and should not be confused with the patent-in-suit. As later discussion highlights, one of Dr Reddy's

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complaints about the validity of the patent-in-suit is that it uses the same compound in respect of which an earlier patent was enjoyed.

14.

The teaching of the patent-in-suit appears from the body of the specification. It instructs that the patent is concerned with the treatment of thromboembolic disorders, which are characterised by abnormal blood clotting. It explains that blood coagulation is a protective mechanism of the organism which helps to seal defects in the wall of the blood vessels quickly and reliably and thus to avoid blood loss. Maintenance of normal haemostasis, or the balance between bleeding and thrombosis (clotting), is subject to a complex regulatory mechanism. Uncontrolled activation of the coagulant system or defective inhibition of the activation processes may cause the formation of local thrombi or embolisms leading to serious thromboembolic disorders. These disorders are the most frequent cause of morbidity in most industrialised countries.

15.

Certain anticoagulants were known from the state of the art at the priority date. These included vitamin K antagonists (like warfarin) and heparins. However, these anticoagulants were known from the prior art to have severe disadvantages. More recent approaches involved factor Xa inhibitors, like rivaroxaban, in the treatment of thromboembolic disorders. The compound patent was registered in respect of rivaroxoban in 2002, although rivaroxaban had not been approved for use as a medicament and was not sold commercially as at the priority date of the patent-in- suit.

16.

The teaching of the patent recognises that oral and a less frequent dosage regime, preferably, once daily, is ideal due to patient compliance and convenience. However, this goal is sometimes difficult to achieve depending on the specific behaviours and properties of the drug substance, especially its plasma

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concentration half-life. In other words, the time it takes for the plasma concentration of the drug in the body to be reduced by 50%. To avoid potential side effects, the drug substance must be applied in no more than a therapeutically effective amount. This means it must be given approximately every half-life.

17.

According to the teaching, the invention of the patent is explained as follows:

"Surprisingly, it has...