Safety-related change to label for Biogen’s Alzheimer's drug Aduhelm approved by FDA

The US Food and Drug Administration (FDA) has approved a safety-related change to the label of Biogen’s Alzheimer's drug Aduhelm (aducanumab).

The new label states that physicians prescribing the drug should ‘inform patients that events of intracerebral haemorrhage greater than 1cm in diameter have been reported infrequently in patients taking Aduhelm, and that the use of antithrombotic or thrombolytic medications while taking Aduhelm may increase the risk of bleeding in the brain’.

Amyloid-related imaging abnormalities (ARIA), such as brain bleeding and swelling, are known side effects of Aduhelm.

In its prescribing information document, the FDA outlines that safety data from two placebo-controlled clinical trials of the Alzheimer’s drug showed ARIA was observed in 41% of Aduhelm-treated patients at a planned dose of 10mg/kg, compared to 10% of patients on placebo.

The new warning is the second safety-related update for Aduhelm’s label, after the FDA made changes in April 2022, which included adding seizures to the list of possible ARIA symptoms.

Biogen withdrew its application for the use of Aduhelm in Europe in April 2022 after discussions with the European Medicine Agency’s (EMA’s) Committee for Medicinal Products for Human Use highlighted that the data provided would not be enough to support a positive opinion on the marketing authorisation of Aduhelm by the regulator.

The EMA explained that, despite Aduhelm reducing amyloid beta in the brain, the connection between this effect and significant clinical improvement had not been verified.

Concerns were also raised by the EMA in December 2021 surrounding the safety of the drug, with the EMA saying in a statement: ‘The studies did not show that the medicine was sufficiently safe as images from brain scans of some patients showed ARIA suggestive of swelling or bleeding in the brain, which could potentially cause harm. Furthermore, it is not clear that the abnormalities can be properly managed in clinical practice.’

In January, Biogen and Eisai’s Alzheimer’s drug, Leqembi (lecanemab-irmb) was approved by the FDA under the accelerated approval pathway

The FDA’s decision was based on phase 2 data showing that Leqembi reduced the accumulation of amyloid beta plaque in the brain, a defining feature of Alzheimer’s disease.

Eisai has also submitted a supplemental biologics application to the FDA for approval under the traditional pathway, the companies said.