Pharmaceutical company Biogen announced in October that they would be seeking regulatory approval from the Food and Drug Administration (FDA) in the United States for aducanumab, an investigational treatment for early Alzheimer’s disease.
This surprise announcements comes after the company ceased two clinical trials (EMERGE and ENGAGE) in March 2019, when interim analyses indicated that it was unlikely that the drug would show significant clinical benefit and so continuing the study was considered futile.
However, additional data from these studies became available resulting in a larger dataset, which included a total of 3,285 patients, 2,066 of whom had the opportunity to complete the full 18 months of treatment. A new extensive analysis of this larger dataset showed a different outcome than that predicted by the interim analysis. In the EMERGE trial, patients who received aducanumab experienced benefits on measures of cognition and function such as memory, orientation, and language. Patients also experienced benefits on activities of daily living including conducting personal finances, performing household chores such as cleaning, shopping, and doing laundry, and independently traveling out of the home. Further, brain imaging demonstrated that amyloid plaque was reduced with low and high dose aducanumab compared to placebo.
Although the EMERGE trial has now met its primary endpoint by showing a reduction in clinical decline, it must be noted that the ENGAGE trial did not. Biogen believes that results from a subset of patients in the ENGAGE trial who received sufficient exposure to high dose aducanumab support the findings from EMERGE.
Aducanumab, which uses antibodies to attach to and remove amyloid plaques from the brain, is not currently available to the public. The next step for Biogen is to submit a Biologics License Application to the FDA in early 2020. The researchers are also planning to initiate a new study, called the aducanumab re-dosing study, available only to those who were actively enrolled in previous aducanumab trials. Although there are a number of study sites in Australia, the clinical trial for this drug will not be open to new patients.
Dementia Australia’s Chief Medical Advisor, Associate Professor Michael Woodward said that if successful, it may only take a year or two before this drug is available in Australia.
“This is the first very promising result for an anti-amyloid therapy, after many years of disappointment. Soon, a new era of administering truly disease-modifying drugs may well begin.”