Rejection of a subsequent patent application does not create a carve-out or exception in an earlier granted patent
Introduction:The case of Cipla Ltd. vs. F. Hoffmann-La Roche Ltd. & Anr. is a significant judgment in Indian patent jurisprudence, especially concerning pharmaceutical patents. The dispute centers around the alleged infringement and validity of a patent related to Erlotinib Hydrochloride, a life-saving cancer drug marketed by Roche as "Tarceva" and by Cipla as "Erlocip." The case involved core issues such as inventive step, application of Section 3(d) of the Patents Act, and the balance between intellectual property rights and public access to affordable medicines.
Factual Background: Roche applied for a patent in the United States on March 31, 1991, for Erlotinib Hydrochloride, which was granted as US Patent '498 on August 5, 1998. Subsequently, Roche filed an application in India on March 13, 1996, which was eventually granted as Indian Patent IN '774 on February 23, 2007. The patent covered Erlotinib Hydrochloride, an EGFR inhibitor used to treat non-small cell lung cancer (NSCLC).
Following further research, Roche discovered that Polymorph B of Erlotinib Hydrochloride exhibited greater thermodynamic stability and enhanced properties. Roche filed a separate patent application for Polymorph B in the United States (granted as US '221) and in India (DEL '507), but the Indian patent application for Polymorph B was rejected by the Controller of Patents. In the meantime, Cipla announced its intention to launch a generic version of Erlotinib Hydrochloride under the name "Erlocip." Roche alleged that Cipla’s product infringed its IN '774 patent.
Procedural Background:Roche approached the Delhi High Court in January 2008 seeking an injunction to restrain Cipla from manufacturing and selling Erlocip. The Single Judge of the Delhi High Court dismissed the interim injunction application on March 19, 2008, primarily considering the public interest involved in making life-saving drugs accessible and affordable to patients. Roche’s appeal against this decision was dismissed by the Division Bench on April 24, 2009. The Supreme Court also refused to entertain Roche’s special leave petition, and the matter proceeded to trial. The Single Judge eventually ruled on the validity of IN '774 and whether Cipla’s activities amounted to infringement.
Issues Involved:The primary issues in the case were whether IN '774 was liable to revocation due to lack of inventive step or being hit by Section 3(d) of the Patents Act, 1970? whether Cipla’s manufacture and sale of Erlocip infringed IN '774; and whether Roche failed to disclose relevant information under Section 8 of the Act, warranting revocation?
Submissions of Parties: Roche contended that IN '774 covered the entire molecule Erlotinib Hydrochloride, inclusive of all its polymorphs. Roche argued that the patented molecule was non-obvious over prior art, demonstrated improved efficacy, and was distinct from previous compounds. The rejection of the Polymorph B application (DEL '507) did not diminish the enforceability or scope of IN '774. Cipla’s manufacture and sale of Erlotinib Hydrochloride, regardless of its form, infringed IN '774.
Cipla argued that IN '774 lacked an inventive step as it was obvious from prior art, particularly Example 51 of EP '226. Cipla maintained that its product was based on Polymorph B of Erlotinib Hydrochloride, which was not covered under IN '774 but rather under the rejected DEL '507 application. Cipla further contended that Roche suppressed information about corresponding foreign patent applications, violating Section 8 of the Act. Cipla also emphasized that Section 3(d) barred patent protection for Polymorph B as it was a mere new form of a known substance without proven enhancement of efficacy.
Discussion of the Court on Subject Matter of the Patent:The court undertook a detailed examination of what constituted the subject matter of IN '774. The court held that IN '774 covered the compound Erlotinib Hydrochloride itself, as described in Claim 1 of the patent, which was independent of the crystalline form (i.e., polymorphic forms A or B). The court interpreted that the subject matter of IN '774 was a chemical compound characterized by its molecular structure, specifically "[6,7-bis(2-methoxyethoxy)quinazolin-4-yl]-(3-ethynylphenyl)amine hydrochloride," and not its physical or crystalline forms.
The court further clarified that polymorphism, which refers to different crystalline arrangements of the same molecule, does not change the chemical identity of the compound. Polymorph A or B merely reflect different solid-state structures of the same chemical molecule, which is Erlotinib Hydrochloride in this case. Since the suit patent claimed the molecule itself, it necessarily covered all polymorphic forms unless the claims explicitly restricted the protection to a specific polymorph, which was not the case with IN '774.
The court noted that Cipla’s argument hinged on conflating the scope of the later DEL '507 application for Polymorph B (which was rejected) with the scope of IN '774. The rejection of DEL '507 under Section 3(d) did not retroactively narrow the coverage of IN '774. The court pointed out that the rejection of a subsequent patent application does not create a carve-out or exception in an earlier granted patent. The subject matter of IN '774 stood independently and remained valid.
The court held that Section 3(d) was intended to prevent the patenting of new forms of known substances that lacked enhanced efficacy, but it was not designed to retrospectively affect the enforceability of valid patents already granted on the parent molecule. Therefore, the invention covered by IN '774 was not barred by Section 3(d) since the patent was granted for the base molecule itself, and not for any specific polymorphic form.
Reasoning and Analysis of the Judge:The Division Bench held that IN '774 granted Roche rights over Erlotinib Hydrochloride, including all its polymorphic forms, as polymorphs are merely different crystalline forms of the same compound. The rejection of DEL '507 under Section 3(d) did not limit the scope of IN '774. Section 3(d) was a filter for patent eligibility but did not operate as a defense against infringement once a valid patent had been granted for the base molecule.
The court emphasized that patent claims should be construed in their plain and ordinary meaning, in accordance with the language of the specification. It rejected Cipla’s argument that Polymorph B should be excluded from the scope of IN '774 merely because a separate patent application for Polymorph B had been rejected under Section 3(d). The court further reasoned that even though polymorphs may exhibit different physical properties, they remain the same chemical entity.
On the issue of non-disclosure under Section 8, the court acknowledged that Roche had not disclosed certain information regarding corresponding foreign applications. However, it exercised discretion under Section 64(1)(m) and refused to revoke the patent solely on this procedural ground, considering that such non-disclosure did not prejudice Cipla’s defense on the merits.
Final Decision:The Division Bench reversed the Single Judge’s decision, holding that Cipla’s Erlocip, being Erlotinib Hydrochloride, infringed Roche’s IN '774 patent. The court upheld the validity of IN '774, ruling that the patent was not liable for revocation based on the grounds raised by Cipla, including lack of inventive step and the Section 3(d) challenge.
Law Settled in this Case:The judgment clarified that once a compound is patented, all polymorphic forms of that compound are covered by the patent unless explicitly excluded. Section 3(d) cannot be used as a defense to infringement; it is applicable at the patent grant stage to filter what constitutes an invention. Procedural lapses such as non-disclosure under Section 8 do not automatically result in patent revocation. The court reaffirmed that patent claims must be interpreted according to their plain meaning and within the context of the specification, without importing limitations from prosecution history or from related but rejected applications.
Case Title: Cipla Ltd. Vs. F. Hoffmann-La Roche Ltd. & Anr.
Date of Order: 27 November 2015
Case No.: RFA(OS) 92/2012 & RFA(OS) 103/2012
Name of Court: Delhi High Court
Name of Judge: Hon'ble Judges Shri Pradeep Nandrajog, Mukta Gupta
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] ,High Court of Delhi
