In a recent decision, the Delhi High Court in Zeria Pharmaceutical Co. Ltd. v. Controller of Patents (C.A.(COMM.IPD-PAT) 452/2022) addressed the hurdles of patenting intermediate compounds in India. The court upheld the rejection of a divisional application for a new intermediate compound, reinforcing strict standards for pharmaceutical patents.
What Are Intermediate Compounds?
In pharma, intermediates are chemical compounds formed along the path to making the final drug. They’re the essential building blocks, but not the end product itself.
Case in Brief
Zeria sought a patent for a novel intermediate compound used in making medicines. The claimed compound differed from known ones by a minor structural change which is swapping an ethoxy group for a methoxy group.
Patent Office’s Objections
The Patent Office raised two main objections:
a. Section 3(d): Zeria didn’t provide data showing that the intermediate led to a final medicine with improved therapeutic efficacy over existing ones.
b. Section 2(1)(ja): The claimed compound did not show an inventive step, as the structural modification was considered obvious to a skilled person.
Court’s Observations
The Court found that the claimed compound was just a minor variation of what’s already known. It emphasized that, under Section 3(d), it’s not enough to show small changes or better process yields. The law requires data proving enhanced therapeutic efficacy in the final drug.
On inventive step, the Court agreed that simply changing one chemical group for another was a routine modification, not an inventive leap.
Key Takeaway
If you’re seeking a patent for an intermediate compound, remember: You must show that it results in a final drug with better therapeutic benefits and not just a marginally different molecule or a more convenient process.
Zeria Pharmaceutical Co. Ltd. v. Controller of Patents (C.A.(COMM.IPD-PAT) 452/2022) Read the judgement copy here