What are the main results from the recent Alzheimer's study by Biogen (NASDAQ:BIIB)?

Biogen (NASDAQ:BIIB) reported that 82.5% of patients in its real-world LEQEMBI study remained stable or improved over 17 months. Nearly 87% of the 427 evaluable U.S. patients chose to stay on the treatment.

How is the disease stage changing for patients taking the Biogen (NASDAQ:BIIB) drug?

Data from Biogen (NASDAQ:BIIB) showed that 75.9% of the tracked patients remained stable. Additionally, 6.6% of patients improved from mild dementia to mild cognitive impairment.

What does the data mean for alternative dosing schedules of the Biogen (NASDAQ:BIIB) treatment?

Biogen (NASDAQ:BIIB) noted that about 81% of patients on a monthly intravenous maintenance dose remained stable or improved. Furthermore, 12 out of 14 patients on a weekly subcutaneous dose stayed stable.

How is the treatment by Biogen (NASDAQ:BIIB) affecting different patient demographics?

Biogen (NASDAQ:BIIB) stated that the drug's benefits were consistent across sex, race, ethnicity, and APOE genotypes. This included consistent results for both APOE ε4 heterozygotes and homozygotes.

What are the safety observations for the Alzheimer's drug developed by Biogen (NASDAQ:BIIB)?

Biogen (NASDAQ:BIIB) reported that amyloid-related imaging abnormalities (ARIA) occurred in 12.3% of patients. The company stated these cases were mostly mild and asymptomatic, aligning with the current U.S. FDA-approved label.

Image for illustrative purposes only. Not a real photo.

Biogen reports 82.5% stability in LEQEMBI study

Written by Heidi Cuthbert Published Jul 14, 2026, 4:21 PM

Biogen and Eisai announced that 82.5% of early Alzheimer's patients taking LEQEMBI remained stable or improved over 17 months.
Safety data showed amyloid-related imaging abnormalities occurred in 12.3% of patients, maintaining consistency with existing FDA label expectations.
The companies are using the ongoing three-year LEADER study to track the real-world efficacy and safety of the treatment.

Biogen (NASDAQ:BIIB) and Eisai reported that 82.5% of LEQEMBI patients remained stable or improved over 17 months.

The real-world LEADER study data presented at AAIC 2026 tracked 427 early Alzheimer’s patients across the United States.

The data showed 75.9% of these patients remained stable, while 6.6% improved from mild dementia to mild cognitive impairment.

Nearly 87% of patients chose to continue treatment, and 12.3% experienced mostly mild amyloid-related imaging abnormalities.

Biogen stated that treatment benefits remained consistent across different patient demographics and specific genetic subgroups.

The companies also reported stable results for smaller subgroups testing monthly intravenous and weekly subcutaneous maintenance doses.