The European Medicines Agency has concluded that the risks linked with use of Biogen and AbbVie's multiple sclerosis drug Zinbryta outweigh its benefits.

The Agency’s Pharmacovigilance Risk Assessment Committee (PRAC) has confirmed that Zinbryta (daclizumab) “poses a risk of serious and potentially fatal immune reactions affecting the brain, liver and other organs.”

Patients could be at risk from the start of treatment and for several months after stopping treatment, and it is not possible to predict which patients will be affected, it said.

Zinbryta is no longer available in hospitals and pharmacies in the EU, because Biogen and AbbVie voluntarily withdrew its marketing authorisation in March, following a stream of reports of serious inflammatory brain disorders - including encephalitis and meningoencephalitis - in patients taking the drug, three of which were fatal.

The drug was first approved in 2016 for treating relapsing forms of multiple sclerosis.

In 2017, its use was restricted to patients who have tried at least two other disease-modifying treatments and cannot be treated with any other MS treatments, following a review of its effects on the liver.