Going Global On Polymorphs

• Published date: 25 March 2024
• Law Firm: Axinn Veltrop & Harkrider
• Author: Mr Ted Mathias, Aziz Burgy and Rebecca L. Clegg

We were so pleased to have the opportunity to address InformaMarkets' 13^th Annual Pharma IPR Conference in Mumbai on legal challenges to polymorph patents. Patents covering one or more crystalline forms of a drug substance at times have presented steep obstacles to generic drug manufacturers' efforts to enter the market. As we sought to make clear through our presentation, however, polymorph patents are of varying strength and susceptible to both noninfringement and invalidity challenges.

We first addressed a divide in the caselaw on how to construe claims reciting polymorphs with specific x-ray powder diffraction or infrared spectroscopy patterns. A bedrock principle of patent law is that a product or process must meet every limitation of a claim to be deemed infringing. Nevertheless, some courts have held that a claim reciting 'characteristic' XRPD peaks at different positions and intensities, for example, can be infringed even if the...