The controversial decision of the National Institute for Health and Clinical Excellence (Nice) to restrict the use of certain drugs for Alzheimer's patients is to be challenged in court.
Two drug companies have announced that they wish to appeal Nice's decision to delay the prescription of treatments including donepezil, rivastigmine and galantamine for newly diagnosed patients.
Eisai and Pfizer have claimed that the process leading up to Nice's decision was unfair and that the decision is "irrational" and not legally sound.
Furthermore, the drug companies are requesting that the watchdog releases a "fully transparent working version of the calculations used in the cost effectiveness model for independent evaluation and comment".
The managing director of Eisai Limited, Dr Paul Hooper, told the BBC: "We are deeply concerned about the way that Nice's decision on treatment recommendations for early Alzheimer's disease was reached. A judicial review is now the only option remaining to us to ensure that Nice reconsiders how it arrived at such flawed conclusions."
Protest marches against the restrictions have been organised across the country by the Alzheimer's Society, which is appealing for doctors to be given greater flexibility in making prescriptions.