A Study to Evaluate the Safety and Tolerability of Long-term Administration of Gantenerumab in Participants With Alzheimer's Disease (AD)

An Open-Label, Multicenter, Rollover Study to Evaluate the Safety and Tolerability of Long-Term Administration of Gantenerumab in Participants With Alzheimer's Disease

The main purpose of the study was to evaluate the safety and tolerability of long-term administration of gantenerumab in participants with AD. All participants who have completed the open-label extensions (OLEs) of studies WN25203 or WN28745 were enrolled in Part 1 of this study. Of these, participants who completed Week 104 visit in Part 1. Participants received open-label gantenerumab by subcutaneous (SC) injection every four weeks (Q4W) at the same dose as administered in the parent studies (part 1)/ Week 104 visit.

Inclusion Criteria:

• Part 1: Participants who completed the open-label extensions (OLEs) of studies WN25203 or WN28745 will be eligible to participate in Part 1 of the study
• Part 2: All participants who have completed Week 104 visit in Part 1 will be eligible for Part 2 of the study
• For Part 1 and Part 2:
• For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive methods that result in a failure rate of <1% per year during the treatment period and for at least 16 weeks after the last dose of study drug
• Agreement to not donate blood or blood products for transfusion for the duration of the study and for 1 year after final dose of study drug
• Availability of a person ('caregiver') who in the investigator's judgement, has frequent and sufficient contact with the participant

Exclusion Criteria:

• Prematurely discontinued from the OLEs of studies WN25203 or WN28745 or from study drug for any reason
• Any medical condition that may jeopardize the participant's safety if he or she continues to receive study treatment
• If the participant is unlikely to benefit from gantenerumab therapy, based on disease progression or other factors, or if study participation is otherwise not in the participant's best interest
• Any investigational treatment other than gantenerumab during or since completion of the OLEs of studies WN25203 or WN28745
• Pregnancy
• Evidence of disseminated leptomeningeal hemosiderosis (i.e., more than three focal leptomeningeal hemosiderosis)
• Evidence of intracerebral macrohemorrhage
• Part 2: Participants who have been discontinued from Part 1 of the study