This matter concerns levocetirizine, which is an enantiomer of cetirizine. The Court held that, at the priority date, it would have been obvious to the skilled person to check whether levocetirizine (which had been individually disclosed before the priority date) had improved pharmacological characteristics compared to the racemic mixture (i.e. cetirizine).

As a rule, resolving a racemic mixture into its individual enantiomers and examining the resulting biological activity is an obvious and predictable first step when researching improvements to a drug with a chiral center, except under certain circumstances. The Court found that Sepracor had not sufficiently shown that one of the exceptions to this rule applies in the present case. The skilled person would thus have acted in the same manner since there was a reasonable expectation of success. The Court therefore invalidated the Belgian part of the patent and, consequently, revoked the Belgian SPC.

A full summary of this case has been published on Kluwer IP Law.


To make sure you do not miss out on regular updates from the Kluwer Patent Blog, please subscribe here.

Kluwer IP Law

The 2022 Future Ready Lawyer survey showed that 79% of lawyers think that the importance of legal technology will increase for next year. With Kluwer IP Law you can navigate the increasingly global practice of IP law with specialized, local and cross-border information and tools from every preferred location. Are you, as an IP professional, ready for the future?

Learn how Kluwer IP Law can support you.

Kluwer IP Law
This page as PDF