Drugmakers Pfizer and Flynn have been fined almost £70 million after they overcharged the NHS for a life-saving epilepsy drug, the competition watchdog has announced.

The Competition and Markets Authority (CMA) said the two pharmaceutical giants “abused their dominant positions” in the market to charge unfairly high prices over a four-year period.

NHS costs for the phenytoin sodium capsules jumped from £2 million in 2012 to £50 million in 2013 after prices were hiked.

The CMA said it has fined Pfizer £63 million and Flynn £6.7 million.

Pfizer has said it will appeal.

These firms illegally exploited their dominant positions to charge the NHS excessive prices and make more money for themselves – meaning patients and taxpayers lost out

The CMA originally issued an infringement decision on the pricing in 2016, finding that the firms broke competition law and handing them fines worth more than £84 million.

The new fine replaces the original decision after Pfizer and Flynn challenged the initial findings with the Competition Appeal Tribunal (CAT).

The CAT partially upheld the findings but it resulted in a second investigation, launched in 2020.

Andrea Coscelli, chief executive of the CMA, said: “Phenytoin is an essential drug relied on daily by thousands of people throughout the UK to prevent life-threatening epileptic seizures.

“These firms illegally exploited their dominant positions to charge the NHS excessive prices and make more money for themselves – meaning patients and taxpayers lost out.

“Such behaviour will not be tolerated, and the companies must now face the consequences of their illegal action.”

A Pfizer spokeswoman said: “Pfizer disagrees with the CMA’s latest infringement decision and will be appealing against it.

“As we have consistently stated throughout this process, ensuring a sustainable supply of our products to UK patients is of paramount importance to us and was at the heart of our decision to divest phenytoin capsules to Flynn Pharma in 2012.

“The Competition Appeal Tribunal and the Court of Appeal both ultimately found in Pfizer’s favour in respect of the CMA’s original decision, which was set aside together with the associated fine.

“We maintain that we approached this divestment, as with all our business operations, with integrity and believe it fully complies with established competition law.”