Novartis AG v Union of India

• Novartis AG filed a patent application for the beta-crystalline form of imatinib mesylate in India
• The compound imatinib was already known and patented in other jurisdictions (Zimmermann patent, 1993)
• India's mailbox application system held the application until the Patents (Amendment) Act 2005 introduced product patents for pharmaceuticals
• The Assistant Controller rejected the application under Section 3(d) as a mere new form of a known substance without enhanced efficacy
• The IPAB (Intellectual Property Appellate Board) upheld the rejection
• Novartis appealed to the Supreme Court, also challenging the constitutional validity of Section 3(d)

1. Whether the beta-crystalline form of imatinib mesylate qualifies as an "invention" under Sections 2(1)(j) and 2(1)(ja) of the Patents Act
2. Whether Section 3(d) is a threshold requirement of patentability separate from novelty and inventive step
3. What "efficacy" means in Section 3(d) when applied to pharmaceutical substances
4. Whether improved bioavailability, thermodynamic stability, or flow properties constitute "enhanced efficacy" under Section 3(d)

• Section 3(d) is an additional threshold for pharmaceutical patents, distinct from novelty and inventive step
• "Efficacy" in the context of a medicine/drug must mean therapeutic efficacy: the ability to produce a desired therapeutic effect
• Improved physical properties (better flow, thermodynamic stability, lower hygroscopicity) do not satisfy Section 3(d) unless they translate into enhanced therapeutic efficacy
• The beta-crystalline form showed 30% improved bioavailability, but Novartis failed to demonstrate this translated into enhanced therapeutic efficacy in patients
• Patent application rejected; IPAB order upheld

The legislature, by inserting Section 3(d), created a higher threshold for pharmaceutical patents on derivatives of known substances. The word "efficacy" must be read as therapeutic efficacy in the pharma context. Properties like stability, bioavailability, or reduced hygroscopicity are not ends in themselves; they must demonstrably translate to better therapeutic outcomes. The provision is India's statutory safeguard against patent evergreening.