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 221AD205

Phase 3b Open-Label, Multicenter, Safety Study of BIIB037 (aducanumab) in Subjects With Alzheimer’s Disease Who Had Previously Participated in the Aducanumab Studies 221AD103, 221AD301, 221AD302 and 221AD205

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2019-004368-22-PT

Enrollment

2400

Registered

2020-04-21

Start date

2020-07-06

Completion date

Unknown

Last updated

2025-02-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Alzheimer's Disease MedDRA version: 20.0 Level: LLT Classification code 10001896 Term: Alzheimers disease System Organ Class: 100000004852

Interventions

Product Name: Aducanumab Product Code: BIIB037 Pharmaceutical Form: Concentrate for solution for infusion INN or Proposed INN: Aducanumab CAS Number: N/A Current Sponsor code: BIIB037 Concentration un

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: - Participant was participating in an aducanumab clinical study at the time of the announcement of early termination (Studies 221AD301, 221AD302, 221AD103 and 221AD205, referred to as “feeder studies”). - Has one care partner who, in the Investigator’s opinion, has adequate contact with the participant as to be able to provide accurate information about the participant’s cognitive and functional abilities. Other protocol defined Inclusion criteria may apply. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 1600 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 800

Exclusion criteria

Exclusion criteria: - Any medical or neurological condition (other than Alzheimer's Disease) that might be a contributing cause of the subject's cognitive impairment. -Stroke or any unexplained loss of consciousness within 1 year prior to Screening. -Clinically significant unstable psychiatric illness in past 6 months. -History of unstable angina, myocardial infarction, advanced chronic heart failure, or clinically significant conduction abnormalities within 1 year prior to Screening. - A seizure event that occurred after the last visit of the feeder study and before Screening for this study. - Evidence of impaired liver function as shown by an abnormal liver function profile at Screening. - History of or known seropositivity for HIV. - Clinically significant systemic illness or serious infection within 30 days prior to or during Screening. - Contraindications to having a brain magnetic resonance imaging (MRI). Other protocol defined Exclusion criteria may apply.

Design outcomes

Primary

Measure	Time frame
Main Objective: The primary objective is to evaluate the long-term safety and tolerability of aducanumab after a wash-out period imposed by discontinuation of feeder studies in participants who had previously received aducanumab (i.e. previously treated participants) or who had previously received placebo (i.e. treatment-naïve participants). ;Secondary Objective: Not applicable;Primary end point(s): 1. Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs) An AE is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product. A SAE is any untoward medical occurrence that at any dose results in death, life-threatening event, requires inpatient hospitalization, significant disability/incapacity or congenital anomaly. 2. Number of Participants with AEs Leading to Treatment Discontinuation or Study Withdrawal An AE is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product. 3. Number of Participants with Amyloid-related Imaging Abnormality-Edema (ARIA-E) Magnetic resonance imaging (MRI) readings will be used to assess ARIA-E severity as mild, moderate and severe. 4. Number of Participants with Amyloid-related Imaging Abnor	—

Measure

Time frame

Main Objective: The primary objective is to evaluate the long-term safety and tolerability of aducanumab after a wash-out period imposed by discontinuation of feeder studies in participants who had previously received aducanumab (i.e. previously treated participants) or who had previously received placebo (i.e. treatment-naïve participants). ;Secondary Objective: Not applicable;Primary end point(s): 1. Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs) An AE is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product. A SAE is any untoward medical occurrence that at any dose results in death, life-threatening event, requires inpatient hospitalization, significant disability/incapacity or congenital anomaly. 2. Number of Participants with AEs Leading to Treatment Discontinuation or Study Withdrawal An AE is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product. 3. Number of Participants with Amyloid-related Imaging Abnormality-Edema (ARIA-E) Magnetic resonance imaging (MRI) readings will be used to assess ARIA-E severity as mild, moderate and severe. 4. Number of Participants with Amyloid-related Imaging Abnor

—

Secondary

Measure	Time frame
Secondary end point(s): Not applicable;Timepoint(s) of evaluation of this end point: Not applicable	—

Countries

Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Italy, Japan, Korea, Republic of, Netherlands, Poland, Portugal, Spain, Sweden, Switzerland, Taiwan, United Kingdom, United States

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026