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Short answer What to know about aducanumab clearance Common questions Related questions SourcesAducanumab-avwa leaves the body slowly, with a half-life of about 25 days, so roughly 4 to 5 months pass after your last infusion before the drug is essentially gone.
It is a monoclonal antibody given as an intravenous infusion every 4 weeks, and it is broken down the way your body handles other large proteins rather than by the liver enzymes or kidneys that clear most pills. Because each dose arrives before the previous one is cleared, blood levels rise over the first several months and then level off. Body weight and the presence of anti-drug antibodies can shift how much drug stays in circulation, so two people on the same schedule may not match exactly. Brain MRI findings such as ARIA can appear or persist while the antibody is still present, which is why scans are often continued for a period after the last dose. Keep a written record of your infusion dates and MRI results, and bring it to any new clinician or emergency visit.
What to know about aducanumab clearance
Common questions
How long does Aducanumab-avwa Injection stay in your system?
Aducanumab-avwa (Aduhelm) is a monoclonal antibody given by IV infusion every 4 weeks. Its elimination half-life is about 25 days, meaning half of what is in your blood is gone in that time. Near-complete clearance takes about 4 to 5 half-lives, so roughly 4 to 5 months after your final dose. Since doses are spaced 4 weeks apart, levels build over the first few months and then reach a steady state. Amyloid-related imaging abnormalities (ARIA), a swelling or bleeding pattern seen on brain MRI, can persist while drug remains, so your care team may keep scanning after you stop. Biogen discontinued Aduhelm in the United States in 2024, and other anti-amyloid options are now used instead.