By Jigyasa Pareek

The Delhi High Court, on December 2, 2025, decided the interim injunction application in Novo Nordisk AS vs Dr. Reddy’s Laboratories Limited & Anr. [CS(COMM) 565/2025] where Nordisk alleged infringement of their patent number 262697 (IN’697), entitled “Acylated GLP-1 Analogs Comprising Non-Proteogenic Amino Acid Residue”.

The suit patent relates to the field of therapeutic peptides and discloses a new protracted GLP-1 analogue known by the INN Semaglutide used in the treatment of conditions like Type 2 Diabetes and obesity. Semaglutide is the Active Pharmaceutical Ingredient (API) in Nordisk’s commercial product ‘Semaglutide compound’, marketed globally as Ozempic, Wegovy and Rybelsus, and in India under the brands Wegovy and Rybelsus. Nordisk alleged that Dr. Reddy’s and OneSource were manufacturing and exporting substantial quantities of the Semaglutide compound and sought an interim injunction to restrain these activities.

The Court held that the Defendants had raised a credible challenge to the validity of the suit patent on the grounds of Section 64(1)(a),(e),(f) and (k) of the Patents Act, 1970, and concluded that the Plaintiff failed to make out a prima facie case for an interim injunction. The Court dismissed the interim injunction application, however (a) maintained the Defendants’ voluntary undertaking not to sell the impugned product in India (given that they did not possess a license to sell in India) and (b) permitted the Defendants to manufacture in India (given that they had a licence to manufacture the impugned drug in India) and export to jurisdictions where Nordisk did not hold patent rights, subject to direction to place on record details of manufacture and sale.

Notably, the Court declined to release the Defendants from their undertaking because the Defendants had commenced manufacturing without “clearing the way” despite being fully aware of the suit patent.

The key issues before the Court were:

• Whether the Defendants should be restrained from manufacturing the impugned drug in India until expiry of the suit patent.
• Whether Semaglutide compound was already disclosed / claimed or obvious from a prior genus patent IN’964 and whether admissions or prosecution history in India and abroad supported that position.

The Defendants raised a ‘Gillette Defence’ to argue non-infringement and prior claiming under Section 64(1)(a), revocation under Sections 64(1)(f) and (k). Their contention was based on the proposition that if a product is already covered, disclosed, claimed and / or enabled by prior patent claims / prior publication, the Defendant cannot be held to infringe a later species patent.

A. Anticipation by prior claiming: Section 64(1)(a)

The Defendants argued that Semaglutide compound claimed in the suit patent was merely a derivative of Example 61 compound enlisted in the genus patent and did not possess any enhanced efficacy over the said compound. They submitted that both patents shared an identical chemical structure, and that the only variation between Example 61 (as reflected in Claim 21 of the genus patent) and Example 4 (as reflected in Claim 23 of the suit patent) was a single substitution of ‘Aib’ [2-methyl Alanine] in place of ‘Ala’ at the 8th position. They contended that this substitution was clearly taught and enabled by the genus patent. They relied on claim language, examples and prosecution history (including Form 27, admissions made on the scope of the genus patent in foreign jurisdiction, Patent Term Extensions (PTE) and Supplementary Protection Certificates (SPC) filings abroad for the genus patent in respect of Semaglutide compound). The Defendants also highlighted that the inventors of both patents were the same and therefore ‘persons in the know’.

Nordisk’s position was that the genus patent did not contain an enabling disclosure of the Semaglutide compound. They argued that coverage is not disclosure. Citing Novartis vs Natco Pharma, Kudos Pharmaceuticals vs Natco Pharma, and FMC vs Best Crop Science Nordisk argued that a broad Markush formula does not amount to disclosure of every species within it, especially when Semaglutide compound was neither exemplified nor specifically taught.

Applying the principles discussed in Boehringer Ingelheim Pharma vs Vee Excel Drugs and Novartis vs Union of India, the Court compared the claims and examples of the two patents and found a person skilled in the art (PSITA) would be led from Example 61read with the relevant claims of the genus patent to make the ‘Aib’ substitution. It held that the Defendants had raised a credible challenge under Section 64(1)(a). The Court also accepted that Nordisk’s PTE/SPC filings abroad constituted admissions that Semaglutide was considered covered by the genus patent.

B. Form 27

The Defendants stressed that Nordisk filed a single Form 27 for both the genus patent and the suit patent for three consecutive years, and that Semaglutide was the only GLP-1 analogue for which Nordisk held a drug import licence. Thus, all revenue declared under the genus patent must necessarily reflect commercial working through Semaglutide, amounting to a clear admission that Nordisk treated Semaglutide as falling within both patents.

Nordisk argued that joint filing of Form 27 is permissible for “related patents” and therefore did not indicate overlap in claim scope. It also asserted that none of the compounds exemplified in the genus patent were ever developed or approved as therapeutic drugs.

The Court rejected Nordisk’s defence unequivocally and held:

• The Forms were a clear admission that the genus patent had been commercially worked through Semaglutide compound, as the Forms for 2021-23 expressly declared working of the genus patent and the only pharmaceutical product on which the deceleration was based on was Semaglutide compound.
• Nordisk’s contrary explanation was “a mere afterthought”, since earlier Forms (2017-2020) stated that the genus patent had “not been worked” pending regulatory approval, while later Forms switched to declaring commercial revenue from the genus patent. Nordisk was bound by these disclosures made before the Patent Office.
• The “related patents” argument was misleading, because the issue was not the filing format but the substance of the declaration: the Forms categorically stated that the genus patent had been worked through Semaglutide.

C. Priority date and the European Opposition Division decision (relevance to prior art)

Nordisk argued that the genus patent could not be treated as a relevant prior art for anticipation (Section 64(1)(e)) or inventive step (Section 64(1)(f)) because its publication date (March 31, 2005) post-dated the suit patent’s priority date (March 18, 2005).

The Defendants relied on the EPO Opposition Division’s decision (25 Jan 2013) which had postdated the priority date of Claim 1 of the corresponding EP application from March 18, 2005 to March 20, 2006 (PCT application filing date) in view of wide-ranging amendments made by Nordisk. They contended that because the EP application formed the basis of priority for the suit patent, the changed priority should also apply to the suit patent, making the genus patent relevant prior art.

Nordisk argued that the EOD’s decision considers the suit patent as novel and inventive after considering the genus patent as prior art should support prima facie validity of the suit patent.

The Court treated priority as a factual question and found that prima facie, the genus patent did qualify as relevant prior art for the purposes of Sections 64(1)(e) and (f). Regarding the EOD’s decision that the suit patent was novel and inventive, the Court opined that the said decision was not binding in India and validity must be assed in accordance with the domestic laws.

D. Anticipation by prior publication: Section 64(1)(e)

The Defendants relied on international search reports which classified the genus patent as a Category X document for the PCT corresponding to the suit patent. Nordisk countered that the search report was being misread, arguing that the cited Category X prior art referred to the Knudsen publication on GLP-1 analogues (such as Exenatide and Liraglutide), and not to the genus patent.

Holding the analysis under Section 64(1)(a) as relevant for determining anticipation under Section 64(1)(e), the Court held that the genus patent did disclose the Semaglutide compound for the PSITA to reproduce it without undue experimentation.

E. Obviousness: Section 64(1)(f) and evergreening

In evaluating inventive step, the Court first identified the PSITA as required under F. Hoffmann-La Roche Ltd. vs Cipla Ltd. Noting that five lead inventors were common to both the genus patent and the suit patent, the Court characterised the relevant PSITA as a ‘person in the know’, who is aware of all the prior arts, having a skill matching with the inventors of the genus patent.

Next, the Court examined the inventive concept of the suit patent, identified the common general knowledge in the prior art documents, compared the prior art documents with the suit patent and determined if Semaglutide compound was obvious to a “person in the know” based on the genus patent and two other cited prior art documents. After a detailed analysis, the Court concluded that on a conjoint reading of the genus patent with the cited prior arts, prima facie, Semaglutide compound would be obvious to the “person in the know”

The Court also accepted the Defendants’ broader allegation of impermissible evergreening. Based on Nordisk’s own pleadings and the foregoing analysis, the Court observed that Semaglutide was already known to Nordisk at the time of filing the genus patent. It held that the compound appeared to have been conceived prior to IN’964, deliberately withheld from disclosure, and later claimed through IN’697, effectively extending the monopoly beyond the term of the genus patent.

F. Balance of convenience and clearing the way

Noting the fact that Nordisk does not manufacture Semaglutide in India but imports the finished product for sale, and the Defendants had already undertaken not to sell the impugned drug within India, the Court found that the commercial interests of both parties stood largely protected pending trial.

the Court declined to release the Defendants from their undertaking because the Defendants had commenced manufacturing without “clearing the way” despite being fully aware of the suit patent. The record showed that after the expiry of the genus patent, the Defendants had sought a manufacturing licence from Nordisk, demonstrating knowledge of Nordisk’s subsisting proprietary claims. Nevertheless, they proceeded with the production in April 2025 without first initiating revocation or non-infringement proceedings and filed the revocation petition only after receiving a cease-and-desist notice.

The Court treated this conduct as a procedural mala fide, consistent with established precedent that a party who knowingly commercialises a product without clearing the way cannot claim favourable equitable consideration at the interim stage. Further, given that the suit patent was due to expire shortly (20 March 2026), the Court held that the Defendants had no balance of convenience in their favour to justify permitting domestic sales pending trial.

Accordingly, while the injunction was refused, the Defendants remained bound by their undertaking not to sell the product in India but were permitted to manufacture and export to jurisdictions where Nordisk did not hold patent rights.