In the intricate domain of patent law, the case of AbbVie Biotherapeutics Inc. & Anr. v. Assistant Controller of Patents stands as a critical examination of the boundaries of permissible claim amendments under India's Patents Act, 1970. Adjudicated by the High Court of Delhi, this case delves into the tension between innovation in biopharmaceuticals and the stringent requirements of patentability, particularly when transitioning from method-of-treatment claims to product claims

 Centered on a patent application for an anti-cMet antibody-drug conjugate (ADC) intended for cancer treatment, the dispute highlights the challenges faced by global innovators in navigating India's patent regime, which excludes methods of treatment from patentability. The judgment reinforces the judiciary's commitment to upholding statutory limits on claim amendments, offering valuable insights for patent practitioners and biopharmaceutical companies seeking to protect their inventions in India.

Detailed Factual Background:
AbbVie Biotherapeutics Inc. and AbbVie Inc., both U.S.-based biopharmaceutical companies, filed a national phase patent application in India on December 17, 2018, under the Patent Cooperation Treaty (PCT) with application number PCT/US2017/033176, dated May 17, 2017. The application claimed priority from a U.S. patent application (US 62/337,796) filed on May 17, 2016.

The subject matter focused on anti-cMet antibody-drug conjugates (ADCs) for treating cMet-overexpressing cancers, such as non-small cell lung cancer (NSCLC). The original specification and 137 claims filed with the PCT application were directed exclusively to methods of treatment, detailing dosing regimens (e.g., 0.15 mg/kg to 3.3 mg/kg, administered every 2 or 3 weeks), patient selection criteria (e.g., IHC scores of 2+ or H-scores of 150+), and therapeutic strategies for resistant tumors. No standalone product or composition claims for the ADC itself were included.

The specification described the ADC's components, including antibody sequences, linkers, and drug-to-antibody ratios, but these were framed within the context of therapeutic use, not as independent inventions. The claims emphasized administration protocols, such as specific dosages (e.g., 2.7 mg/kg for NSCLC adenocarcinoma) and combination therapies with agents like erlotinib or PD1 inhibitors. On May 15, 2020, AbbVie requested examination of the application, and the First Examination Report (FER), issued on November 5, 2020, raised objections under Section 2(1)(j) for lack of industrial applicability and Section 3(i) for non-patentability of method-of-treatment claims.

In response, AbbVie submitted amended claims on May 5, 2021, via Form 13, reducing the claim set to eight, with Claim 1 as an independent product claim for the anti-cMet ADC (conjugated with monomethyl auristatin E) and Claims 2–8 as dependent claims, including pharmaceutical compositions.

A hearing was scheduled for December 6, 2022, where the Patent Office reiterated objections under Sections 2(1)(j) and 3(i), and added a new objection under Section 59(1), alleging that the amended claims broadened the scope of the original claims. AbbVie filed written submissions on January 19, 2023, defending the amendments. However, on July 31, 2023, the Assistant Controller refused the application, citing violations of Sections 2(1)(j), 3(i), and 59(1). A subsequent review petition filed on October 26, 2023, under Section 77(1)(f) was dismissed on March 6, 2024, as time-barred, prompting AbbVie to appeal to the Delhi High Court.

Detailed Procedural Background:
The procedural journey began with the filing of the PCT national phase application on December 17, 2018, at the Indian Patent Office in Delhi. Following the request for examination on May 15, 2020, the FER was issued on November 5, 2020, identifying deficiencies in industrial applicability and patentability due to the method-of-treatment nature of the claims. AbbVie's response on May 5, 2021, included a new set of eight claims, shifting the focus to the ADC as a product. The Patent Office scheduled a hearing for December 6, 2022, and communicated additional objections, including the impermissibility of the amendments under Section 59(1).

After the hearing, AbbVie's written submissions on January 19, 2023, sought to justify the amendments as within the scope of the original specification. Despite these efforts, the Assistant Controller's order on July 31, 2023, rejected the application, finding the amended claims impermissible and the original claims non-patentable. AbbVie's review petition, filed on October 26, 2023, was dismissed on March 6, 2024, due to a delay beyond the statutory period. Aggrieved, AbbVie filed an appeal under Section 117A of the Patents Act, registered as C.A.(COMM.IPD-PAT) 44/2023, before the Delhi High Court. The appeal was heard by Hon'ble Mr. Justice Amit Bansal, who delivered the judgment on March 25, 2025, after considering arguments from both parties and reviewing the case records.

Issues Involved in the Case:
The case raised several critical issues for adjudication. First, whether AbbVie's proposed amendments, converting method-of-treatment claims to product claims for an anti-cMet ADC, were permissible under Section 59(1) of the Patents Act, which limits amendments to disclaimers, corrections, or explanations. Second, whether the amended claims fell within the scope of the original specification and claims, as required by Section 59(1). Third, whether the original method-of-treatment claims were non-patentable under Section 3(i) and lacked industrial applicability under Section 2(1)(j). Fourth, whether the Controller's rejection of the amendments as an attempt to circumvent statutory restrictions was justified. Finally, whether judicial precedents supported allowing such amendments in the context of PCT national phase applications.

Detailed Submission of Parties:
AbbVie's counsel argued that the amendments were permissible under Sections 57 and 59 of the Act, asserting that amendments could be made at any time during the patent application's lifecycle, including during the national phase. They contended that the amended product claims, directed to the anti-cMet ADC, were disclosed in the original specification, which detailed the ADC's structure, linkers, and antibody sequences.

Thus, the amendments complied with Section 59(1) by remaining within the scope of the original disclosure. AbbVie further argued that the Controller's objections under Sections 2(1)(j) and 3(i) should be waived, as the amended claims avoided method-of-treatment limitations. They relied on Allergan Inc. v. Controller of Patents (2023 SCC OnLine Del 295), where the court permitted amendments from method-of-treatment to product claims, arguing that the present case was analogous.

The Assistant Controller's counsel countered that the amendments violated Section 59(1) by broadening the scope of the original claims. They noted that the PCT application's 137 claims and the national phase claims were exclusively method-of-treatment claims, with no standalone product claims. Under Section 138(4), national phase applications must mirror the PCT claims, allowing only deletions, not additions of new claim types.

The amended claims, covering the ADC and compositions without treatment limitations, expanded protection to all uses, unlike the original claims' focus on specific cancer treatments. The Controller argued that this constituted impermissible broadening, citing Nippon A & L Inc. v. Controller of Patents (2022 SCC OnLine Del 1909). They defended the impugned order as well-reasoned, asserting that the original claims were non-patentable under Section 3(i) and lacked industrial applicability under Section 2(1)(j).

Detailed Discussion on Judgments Cited by Parties:

The court considered several precedents cited by the parties, each addressing the scope of amendments and patentability:

• Allergan Inc. v. Controller of Patents, 2023 SCC OnLine Del 295: AbbVie relied on this case, where the Delhi High Court allowed amendments from method-of-treatment to product claims in a PCT application. The court found the amendments within the specification's scope, as they pertained to the same disease. However, the judgment did not explicitly analyze whether the amendments were disclaimers, corrections, or explanations, limiting its applicability. In the present case, the court distinguished Allergan, noting that AbbVie's amended claims omitted disease-specific limitations, broadening the scope beyond the original NSCLC focus.
   
• Nippon A & L Inc. v. Controller of Patents, 2022 SCC OnLine Del 1909: Cited by the Controller, this case clarified Section 59(1)'s requirements, stating that amendments must be disclaimers, corrections, or explanations, incorporate actual facts, and not claim matter beyond the original specification or broaden the claim scope. The court's framework was pivotal, guiding the analysis that AbbVie's shift to product claims expanded protection impermissibly, as the original claims were limited to therapeutic use.
   
• Ovid Therapeutics v. Controller of Patents & Designs, 2024 SCC OnLine Del 875: This case, following Nippon, involved a patent application with method-of-treatment and composition claims. The Controller rejected amendments to composition-only claims for broadening the scope by omitting disease-specific limitations. The court upheld the rejection, finding the amendments violated Section 59(1). This precedent was directly applicable, as AbbVie's amendments similarly removed NSCLC limitations, expanding the ADC's protection to all uses.
   
• Novartis AG v. Union of India, (2013) 6 SCC 1: The Supreme Court's ruling, cited by the court, emphasized that Indian patent law discourages artful claim drafting to broaden protection beyond an invention's intrinsic worth. This principle supported the Controller's view that AbbVie's amendments were a strategic attempt to sidestep Section 3(i)'s exclusion of method-of-treatment claims, reinforcing the rejection under Section 59(1).

These judgments collectively underscored the strict interpretation of Section 59(1), prioritizing fidelity to the original specification and claims over strategic amendments.

Detailed Reasoning and Analysis of Judge:
Court's analysis was rooted in a rigorous interpretation of the Patents Act and judicial precedents. The court began by examining the original specification and claims, which focused exclusively on methods of treating cMet-overexpressing cancers, particularly NSCLC, with specific dosing regimens and patient criteria. The specification described the ADC's components but only in the context of therapeutic use, not as a standalone product. The 137 PCT claims and national phase claims were similarly method-centric, with no independent product claims.

The court then assessed the amended claims, which shifted to a product claim for the anti-cMet ADC (with monomethyl auristatin E) and included composition claims. These amendments eliminated references to dosing, patient populations, and cancer types, seeking protection for the ADC itself across all uses. The court identified four key differences: the amended claims covered a product, not a method; omitted treatment limitations; added new composition claims; and removed disease-specific references. These changes, the court held, broadened the scope significantly, as the original claims protected the ADC only in specific therapeutic contexts, while the amended claims sought a monopoly over the ADC universally.

Applying Section 59(1), as interpreted in Nippon, the court evaluated whether the amendments were disclaimers, corrections, or explanations. A disclaimer narrows scope by excluding subject matter, but AbbVie's amendments expanded protection, disqualifying them as disclaimers. An explanation clarifies existing claims, but the shift to product claims was a transformation, not a clarification. A correction addresses clerical errors, not substantive changes like altering claim categories. The court concluded that the amendments were none of these, as they introduced new subject matter (composition claims) and exceeded the original specification's scope, violating Section 59(1).

The court distinguished Allergan, noting that the amendments there remained disease-specific, unlike AbbVie's, which removed NSCLC limitations. Ovid and Nippon reinforced that broadening amendments are impermissible, as they confer additional protection beyond the original disclosure. The court also invoked Novartis to caution against artful drafting, viewing AbbVie's amendments as an attempt to circumvent Section 3(i)'s bar on method-of-treatment claims. The original claims, being method-centric, were correctly deemed non-patentable under Section 3(i) and lacking industrial applicability under Section 2(1)(j), as they did not fit the Act's definition of an invention.

The Controller's findings—that the amendments were a "clever move" to avoid Section 59(1) and that the original claims were non-patentable—were upheld as well-reasoned. The court found no infirmity in the impugned order, dismissing AbbVie's appeal.

Final Decision:
The Delhi High Court dismissed the appeal, upholding the Assistant Controller's order dated July 31, 2023, refusing the patent application under Section 15 of the Patents Act. The court affirmed that the proposed amendments violated Section 59(1) by broadening the claim scope, and the original method-of-treatment claims were non-patentable under Section 3(i) and lacked industrial applicability under Section 2(1)(j). The Registry was directed to supply a copy of the order to the Controller General of Patents, Designs, and Trade Marks for compliance. The judgment was delivered on March 25, 2025.

Law Settled in This Case:
This case establishes several key principles in Indian patent law. First, amendments under Section 59(1) must be limited to disclaimers, corrections, or explanations, and must not broaden the scope of the original claims or introduce matter beyond the specification's disclosure. Second, converting method-of-treatment claims to product claims, especially when the original claims lack standalone product protection, violates Section 59(1) if it expands protection to new uses or categories.

Third, method-of-treatment claims are non-patentable under Section 3(i) and lack industrial applicability under Section 2(1)(j), reinforcing India's exclusion of therapeutic methods. Fourth, the specification's intent governs the permissible scope of amendments, and strategic drafting to circumvent statutory exclusions is impermissible. Finally, judicial scrutiny ensures fidelity to the original disclosure, protecting the patent system's integrity.

Case Title:AbbVie Biotherapeutics Inc. & Anr. v. Assistant Controller of Patents
Date of Order:March 25, 2025
Case No. C.A.(COMM.IPD-PAT) 44/2023
Neutral Citation 2025:DHC:2594
Name of Court:High Court of Delhi at New Delhi
Name of Judge:Hon'ble Mr. 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