The UK drug industry is taking legal action over new limits on the price of medicines which companies say will "deny treatments to patients suffering from rare diseases".
An unusual challenge to the authority of the National Institute for Health and Care Excellence (Nice), which authorises spending by the NHS on new treatments, has been launched by the Association of the British Pharmaceutical Industry (ABPI).
The trade body has applied for a judicial review of a decision taken by NHS England and Nice in March that held back the automatic funding of new drugs set to cost more than £20m a year in their first three years of use.
Mike Thompson, chief executive of the ABPI, said the new arrangements "will delay access to cost-effective medicines" and leave patients suffering from rare diseases without treatment.
"After many months of raising concerns with Nice, NHS England and the Department of Health and offering to work constructively on alternative proposals, we have applied to formally challenge these proposals in court.," he said.
"We believe this to be the right course of action due to the potential damage these changes will cause to NHS care and on our ability to research, develop and use new medicines here in the UK."
Analysis found that around one in five new medicines, including for conditions including cancer, heart disease and diabetes, will be affected by the plans, said the APBI.
The association added that it is important to challenge new procedures "before the first medicines get caught in the system" to avoid uncertainty for patients.
In a judicial review, a court reviews the lawfulness of an action or decision taken by a public body.
Nice told The Independent it would not yet comment on the action by the ABPI.
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