Pharmaceutical firms Pfizer and Flynn Pharma have been accused by the UK’s competition watchdog of charging “excessive and unfair” prices for an anti-epilepsy drug.
Phenytoin sodium capsules, used by 50,000 people in Britain, are made by Pfizer and sold by Flynn.
Pfizer said it was co-operating with the Competition and Markets Authority.
When Pfizer made the drug under its Epanutin brand name, the NHS spent about £2.3m on the drug, the CMA said.
This amount soared to £50m in 2013.
The CMA said Pfizer sold UK distribution rights to Flynn in 2012, but continued to make and supply the drug to the company.
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