In this article 4523.T-JP BIIB Follow your favorite stocks CREATE FREE ACCOUNT Eisai | via Reuters European drug regulators on Friday rejected the Alzheimer's treatment Leqembi from Biogen and Eisai , creating another hurdle for the companies as they scramble to boost uptake of the therapy in the U.S.

The European Commission, the EU's executive body, has a final say in Leqembi's approval. But it almost always follows the drug regulator's recommendations. In a statement , Eisai said it is "extremely disappointed" by the regulator's negative recommendation.

The company added that it will seek a re-examination of the decision. Shares of Biogen fell nearly 7% in premarket trading Friday. Japanese drugmaker Eisai's stock was essentially flat.

The U.S. Food and Drug Administration last year approved Leqembi, which has seen a sluggish rollout due to bottlenecks related to diagnostic test requirements and regular brain scans, among other issues.

Leqembi has also won regulatory approvals in other countries such as Japan, South Korea, China and Israel. The drug was considered a breakthrough for a progressive disease that has proven notoriously hard to treat. It is a monoclonal antibody that slows the progression of the disease in patients at the early stages of it.

The European Medicines Agency's human medicines committee recommended against granting marketing authorization for Leqembi. In a statement, the committee said Leqembi's effect on delaying cognitive decline does not outweigh .