In the intricate world of pharmaceutical patents, where innovation meets the crucible of legal scrutiny, the case of Boehringer Ingelheim Pharma GmbH & Co. KG Vs. Vee Excel Drugs and Pharmaceuticals Pvt. Ltd. and connected matters, decided by the Delhi High Court on March 29, 2023, stands as a landmark exploration of patent validity and interim relief. This batch of six suits revolves around Indian Patent No. 243301 (IN '301), covering Linagliptin, a critical drug for type 2 diabetes management. Boehringer Ingelheim, a global pharmaceutical leader, sought to restrain multiple Indian generic manufacturers from producing and selling Linagliptin, alleging infringement of IN '301.

The defendants, including Vee Excel, Alkem Laboratories, Micro Labs, Natco Pharma, and Mankind Pharma, countered by challenging the patent's validity, alleging it was an impermissible attempt to extend monopoly rights beyond the expired genus patent, IN '719. The Delhi High Court grappled with complex issues of prior claiming, evergreening, and public interest, ultimately denying interim injunctions. This case study delves into the factual and procedural intricacies, legal issues, parties' arguments, judicial precedents, the court's reasoning, and the broader implications, offering a vivid narrative of innovation under legal siege in India's patent regime.

Detailed Factual Background
Boehringer Ingelheim Pharma GmbH & Co. KG, a Germany-based pharmaceutical giant, and its Indian subsidiary, Boehringer Ingelheim (India) Pvt. Ltd., are renowned for developing and marketing innovative drugs. The plaintiffs hold Indian Patent No. 243301, granted on October 5, 2010, titled "8-(3-Aminopiperidin-1-yl)-Xanthine Compounds," covering Linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor used to treat type 2 diabetes. Marketed under brands like Trajenta, Trajenta Duo, and Ondero, Linagliptin was launched in India in 2012 and 2014, achieving significant commercial success.

The patent, valid until August 18, 2023, grants Boehringer exclusive rights under Section 48 of the Patents Act, 1970, to prevent unauthorized manufacture, use, sale, or importation. The plaintiffs emphasized that no pre-grant or post-grant oppositions were filed against IN '301, and it was upheld in China, reinforcing its global validity. Boehringer's substantial R&D investments, coupled with its licensing agreements with Lupin and Eli Lilly, underscored its commercial stake in Linagliptin.

The defendants, Indian pharmaceutical companies including Vee Excel Drugs and Pharmaceuticals Pvt. Ltd., Alkem Laboratories Ltd., Micro Labs Limited, Natco Pharma Limited, and Mankind Pharma Limited, are engaged in manufacturing and selling generic Linagliptin 5 mg tablets. Boehringer alleged that these products infringed IN '301, as they contained Linagliptin without authorization. The plaintiffs highlighted prior successful enforcement actions against other infringers, such as MSN Laboratories, before the Himachal Pradesh High Court. A key contention was the relationship between IN '301 and an earlier patent, IN '719, titled "Xanthine Compounds," a genus patent covering a Markush formula that expired on February 21, 2022.

The defendants argued that Linagliptin was covered and claimed in IN '719, rendering IN '301 an invalid attempt at evergreening to extend monopoly rights. They pointed to Boehringer's admissions in prior litigations and regulatory filings, including Form 27 statements, which listed identical Linagliptin products for both patents, suggesting that IN '301 duplicated IN '719's scope.

Boehringer countered that IN '301 was a species patent, claiming specific commercial embodiments of Linagliptin developed through further research after IN '719's filing. They argued that Linagliptin was neither specifically claimed nor disclosed in IN '719, and the genus patent's Markush formula did not anticipate IN '301's inventive step. The plaintiffs also noted that the defendants began commercializing Linagliptin only after IN '719's expiry, but this did not negate infringement of IN '301, which remained valid until August 2023. The defendants, in turn, emphasized public interest, highlighting their significantly cheaper Linagliptin products compared to Boehringer's imported drugs, crucial for affordability in a country with high diabetes prevalence.

Detailed Procedural Background
The dispute unfolded through six suits filed before the Delhi High Court: CS(COMM) 239/2019, CS(COMM) 240/2019, CS(COMM) 236/2022, CS(COMM) 237/2022, CS(COMM) 238/2022, and CS(COMM) 296/2022. Boehringer sought permanent injunctions to restrain the defendants from infringing IN '301, alongside damages and other reliefs.

Each suit was accompanied by applications for interim injunctions under Order XXXIX, Rules 1 and 2 of the Code of Civil Procedure (CPC), 1908, specifically I.A. 6797/2019, I.A. 6802/2019, I.A. 5801/2022, I.A. 5806/2022, I.A. 5811/2022, and I.A. 7109/2022. The defendants filed written statements and counterclaims seeking revocation of IN '301 under Section 64 of the Patents Act, 1970, alleging prior claiming, lack of inventive step, and evergreening.

In CS(COMM) 239/2019 and CS(COMM) 240/2019, summons were issued on May 10, 2019, with ad interim injunctions granted, restraining Vee Excel from manufacturing Linagliptin tablets. These orders persisted until the final judgment. For CS(COMM) 236/2022, CS(COMM) 237/2022, and CS(COMM) 238/2022, summons were issued on April 19, 2022, with a pro-tem arrangement agreed upon, prohibiting the defendants from manufacturing or selling Linagliptin, except for existing stock, pending disclosure of stock details. A similar arrangement was adopted in CS(COMM) 296/2022 on May 9, 2022. The court heard arguments on multiple dates in January 2023, reserving judgment on January 27, 2023, and delivering it on March 29, 2023.

Issues Involved in the Case

The case presented several pivotal legal questions at the nexus of patent law and interim relief:

• Whether the age of IN '301, an "old" patent nearing expiry, warranted a presumption of validity for interim injunction purposes?
• Whether the absence of pre-grant or post-grant oppositions, or the belated filing of revocation petitions, strengthened the plaintiffs' claim to interim relief?
• Whether the defendants raised a credible challenge to IN '301's validity, particularly on grounds of prior claiming under Section 64(1)(a), evergreening, or non-compliance with Section 3(d) of the Patents Act?
• Whether Boehringer's assertions that Linagliptin was covered by both IN '719 and IN '301 in prior litigations estopped them from claiming it was only specifically claimed in IN '301?
• Whether denying an interim injunction would cause irreparable harm to Boehringer, or if monetary damages could suffice, given its licensing arrangements?
• How public interest, particularly access to affordable anti-diabetes drugs, should influence the court's equitable discretion in granting interim relief?

• Detailed Submission of Parties
  • Boehringer's counsel argued that IN '301, granted in 2010 and valid until August 2023, conferred exclusive rights under Section 48, which the defendants violated by manufacturing Linagliptin without licenses. They highlighted:
    • The patent's enforcement against other infringers, its global validity, and the absence of oppositions in India.
    • Cited National Research Development Corp. of India vs. Delhi Cloth & General Mills (1979 SCC OnLine Del 206) to argue that an old, worked patent should be presumed valid for interim relief.
    • Contended that IN '719, a genus patent, did not specifically claim or disclose Linagliptin, as its Markush formula was too broad, and IN '301's claims were distinct, supported by further research.
    • Dismissed the defendants' reliance on Form 27 filings as irrelevant and rejected evergreening allegations.
    • Cited FMC Corporation vs. Best Crop Science LLP (2021) 87 PTC 217 to assert the defendants' burden to establish a credible challenge.
    • Argued that the Patents Act's compulsory licensing provisions addressed affordability and that monetary damages could not compensate for market erosion.
  • The defendants' counsel argued that:
    • IN '301 was invalid under Section 64(1)(a) for prior claiming, as Linagliptin was covered in IN '719, which expired in February 2022.
    • They cited Boehringer's admissions, Form 27 filings, and a 2008 reply to the Patent Office as evidence of coverage.
    • Invoked Section 13(4) and Bishwanath Prasad Radhey Shyam vs. Hindustan Metal Industries (AIR 1982 SC 1444) to argue no presumption of validity exists.
    • Accused Boehringer of evergreening, citing AstraZeneca AB vs. Intas Pharmaceuticals Ltd. (MANU/DE/1939/2020) and its Division Bench affirmation.
    • Emphasized public interest, highlighting cheaper Linagliptin and Boehringer's licensing and importation practices.
    • Alleged non-disclosure of material information under Section 8.
• Detailed Discussion on Judgments Cited by Parties
  • Bishwanath Prasad Radhey Shyam vs. Hindustan Metal Industries, AIR 1982 SC 1444
  • National Research Development Corp. of India vs. Delhi Cloth & General Mills, 1979 SCC OnLine Del 206
  • F. Hoffmann-La Roche Ltd. vs. Cipla Ltd., 2008 SCC OnLine Del 382
  • F. Hoffmann-La Roche Ltd. vs. Cipla Ltd., ILR (2009) Supp. (2) Delhi 551
  • AstraZeneca AB vs. Intas Pharmaceuticals Ltd., MANU/DE/1939/2020
  • AstraZeneca AB vs. Intas Pharmaceuticals Ltd., (2021) 87 PTC 374 (DB)
  • Novartis AG vs. Union of India, (2013) 6 SCC 1
  • Novartis AG vs. Natco Pharma Limited, 2021 SCC OnLine Del 5340
  • FMC Corporation vs. Best Crop Science LLP, (2021) 87 PTC 217
  • FMC Corporation vs. GSP Crop Science Private Limited, 2022 SCC OnLine Del 3784
  • Bristol-Myers Squibb Company vs. J.D. Joshi, MANU/DE/1889/2015
  • Smith vs. Grigg Ltd., (1924) 41 RPC 149 (UK)
• Detailed Reasoning and Analysis of Judge
  • The court applied the triple test for interim injunctions—prima facie case, balance of convenience, and irreparable harm.
  • Framed four key issues:
    • Whether old patents presume validity.
    • Whether lack of oppositions or belated revocation petitions favored Boehringer.
    • Whether the defendants raised a credible challenge.
    • Whether the balance of convenience supported an injunction.
  • The court relied on Section 13(4) and case law to hold no presumption of validity exists for any patent.
  • Found a credible challenge to IN '301's validity under Section 64(1)(a) based on evidence and admissions.
  • Held the balance of convenience favored the defendants, emphasizing public interest and affordable access to medication.
  • Distinguished the Himachal Pradesh High Court's ruling in Boehringer vs. MSN Laboratories.
• Final Decision
  • The Delhi High Court dismissed all interim injunction applications on March 29, 2023, with costs of Rs. 2,00,000 to each defendant and Rs. 2,00,000 to the Delhi High Court Legal Services Committee.

Case Title: Boehringer Ingelheim Pharma GmbH Vs Vee Excel Drugs and Pharmaceuticals Pvt. Ltd.
Date of Order: March 29, 2023
Case No.: CS(COMM) 239/2019
Neutral Citation: 2023:DHC:2249
Name of Court: High Court of Delhi
Name of Hon'ble Judge: Justice Amit Bansal

Disclaimer: The information shared here is intended to serve the public interest by offering insights and perspectives. However, readers are advised to exercise their own discretion when interpreting and applying this information. The content herein is subjective and may contain errors in perception, interpretation, and presentation.

Written By: Advocate Ajay Amitabh Suman, IP Adjutor - Patent and Trademark Attorney
Email: ajayamitabhsuman@gmail.com, Ph no: 9990389539