Lead sponsor
Biogen
15 Alzheimer’s disease and related dementias trials led. Source: ClinicalTrials.gov, as of July 21, 2026.
15
Trials led
1
Ongoing
8,071
Total enrollment
814
Sites
Distinct sites across this sponsor's lead trials. A site running several of them counts once, matching the map. Total enrollment sums each trial's reported enrollment, whether planned or actual.
Portfolio
How this sponsor's trials break down
Trials by phase
Phase 1
7
Phase 2
4
Phase 3
4
Trials by status
Active, not recruiting
1
Completed
5
Terminated
9
Trials led
TrialEligibility highlightPhaseStatusEnrollment
A Study to Evaluate Safety and Tolerability of Aducanumab in Participants With Alzheimer's Disease Who Had Previously Participated in the Aducanumab Studies 221AD103, 221AD301, 221AD302 and 221AD205Age 50-90Ph 3Terminated1,696
Single Ascending Dose Study of BIIB037 in Participants With Alzheimer's DiseaseAlzheimer's diseasePh 1Completed53
Extension Study of BIIB092 in Participants With Progressive Supranuclear Palsy (PSP) Who Participated in CN002003Study partner/caregiver requiredPh 1Terminated47
Single-Ascending-Dose Study of BIIB076 in Healthy Volunteers and Participants With Alzheimer's DiseaseMCI due to ADPh 1Completed46