Daewoong Pharmaceutical Co. Ltd. v. Controller General Of Patents Designs And Trademarks

When a pharmaceutical company spends millions developing a new physical form of an existing drug, the last thing it wants to hear is that its innovation is not "new enough" to deserve a patent. Yet this is the exact wall Daewoong Pharmaceutical ran into when its Indian patent application for a crystalline form of compound c28 was rejected. The case shines a spotlight on one of the most debated provisions in Indian patent law, Section 3(d), and asks a question every founder in the life sciences space must grapple with: when does a physical improvement to a known compound cross the line from incremental tinkering to genuine therapeutic advancement?

Daewoong Pharmaceutical Co. Ltd., along with another applicant, filed Indian Patent Application No. 201817048074 seeking protection for a crystalline form of a compound referred to as c28. The application was examined and refused by the Controller General of Patents, Designs and Trade Marks. The rejection rested squarely on Section 3(d) of the Patents Act, 1970, the provision designed to prevent evergreening, the practice of securing fresh patents on minor variations of existing drugs without any real therapeutic gain. The Controller treated the crystalline form as a known substance and concluded that Daewoong had not demonstrated enhanced therapeutic efficacy over what already existed. Aggrieved by this refusal, Daewoong approached the High Court, seeking not just a reversal but also permission to introduce fresh technical data into the record.

Daewoong's central argument was that the crystalline form of compound c28 was not merely a cosmetic change. The company sought to bring in additional data highlighting superior physical and chemical properties, including improved stability and better dissolution rates, to argue that the new form offered tangible advantages. On the other side stood the Controller General, defending the rejection on the ground that Section 3(d) demands more than physical or physicochemical improvements; it requires evidence of significantly enhanced therapeutic efficacy. The legal friction was sharp: Daewoong wanted the court to weigh new evidence submitted after filing, while the patent office insisted that the application, as originally presented, failed to clear the statutory bar. The High Court stepped into this standoff and accepted Daewoong's application seeking to file additional documents, but it did not stop there. The court framed two pivotal issues that would determine the fate of the patent: first, whether post-filing supplementary data is even admissible in such appeals, and second, whether the crystalline form ultimately satisfies the requirements of Section 3(d).

The High Court's decision was a mixed outcome, reflecting the complexity of the dispute. On the procedural front, the court allowed Daewoong the opportunity to file additional documents, signaling openness to considering supplementary technical evidence. However, by framing the two critical legal questions, the court made clear that admissibility of post-filing data and substantive compliance with Section 3(d) would both be rigorously tested. The court leaned on Section 3(d) of the Patents Act, 1970, the very provision that had triggered the original rejection, and signaled that any patent for a new form of a known substance must demonstrate a meaningful enhancement in therapeutic efficacy, not just better stability on a shelf or faster dissolution in a lab. The mixed outcome left Daewoong with a narrow path forward: even with additional evidence accepted, the company still faced the uphill battle of proving that its crystalline form delivered a significant therapeutic leap.

For founders and IP professionals in pharmaceuticals and life sciences, this case delivers a hard-edged lesson. First, do not assume that a new physical form, whether crystalline, amorphous, or a different salt, will automatically qualify for patent protection in India. Section 3(d) is unforgiving, and the bar of "enhanced therapeutic efficacy" is the gatekeeper. Second, build your patent application around therapeutic outcomes from day one. Stability, dissolution rates, and other physicochemical improvements are useful supporting evidence, but they are not substitutes for clinical or pharmacological proof that the new form does something meaningfully better for patients. Third, be cautious about relying on post-filing data to rescue a weak application. While the court in this case permitted additional documents, the