The Court of Appeal allows the CMA and Pfizer and Flynn’s Appeals in ‘Phenytoin’ Litigation

19/06/26

The Court of Appeal handed down judgment today in the long-running ‘Phenytoin’ litigation, relating to the pricing of phenytoin sodium capsules, used in the treatment of epilepsy. The Court (Green LJ, Zacaroli LJ and Snowden LJ) allowed the CMA’s appeal against the CAT’s decision on all grounds and allowed both Pfizer and Flynn’s appeals against the CAT’s decision on procedural fairness grounds. 

The CMA first found that Pfizer and Flynn had infringed the Chapter II prohibition in their pricing of phenytoin sodium capsules in December 2016. That decision was appealed by Pfizer and Flynn and set aside by the CAT in 2018, which was upheld by the Court of Appeal, before being remitted to the CMA. The CMA’s further decision, in July 2022, again found infringements in respect of the pricing of phenytoin sodium capsules. 

In 2024, the CAT upheld the appeals of Pfizer and Flynn against the CMA’s further decision. The CAT also, however, exercised its jurisdiction to remake the CMA’s decision and found infringements of the Chapter II prohibition by Pfizer and Flynn. Pfizer and Flynn appealed against the CAT’s remade findings of infringement, on the grounds that the CAT (i) lacked jurisdiction to make these findings, and/or (ii) that they should be set aside for procedural unfairness. The CMA also sought permission to appeal against the CAT’s decision to set aside the CMA’s July 2022 decision, on several grounds. 

In its judgment handed down today, the Court of Appeal granted the CMA permission to appeal and upheld its appeal against the CAT’s decision on all grounds. It also allowed both Pfizer and Flynn’s appeals on procedural fairness grounds. The Court has invited the parties to make submissions on whether the CMA’s decision should be reinstated and on any consequential issues as to penalties, which will be addressed in a separate ruling. 

The judgment is here.