June 22 was my last Lecanemab infusion. That was my 18th infusion.
It can take as long as two months to clear Lecanemab from your body. As I quickly approach the three-month mark, my side effects continue. My primary side effect is chills in my arms and legs. These chills are frequent (several each hour) and extreme. I wear fleece pants and a fleece jacket to counteract them. Some of the chills are so bad they are accompanied by a strong shiver.
I have searched every nook and cranny of the internet looking for any mention of lingering issues after stopping Lecanemab. My research has found limited and indirect information.
While Lecanemab is designed to cause localized immune activity in the brain, it is a systemic monoclonal antibody. I wonder if it triggered a prolonged or delayed immune system response or systemic inflammation. One cause of chills without fever is an immune system fighting off a virus or bacterial infection.
Duke Health has not been able to find another cause of the chills.
I asked on Reddit this morning for similar experiences. Likewise, if any readers of this post have knowledge of illness continuing after stopping Lecanemab infusions, please let me know.
This is such an important part of treatment that trial results can’t really capture. A drug can have a measurable effect on disease progression and still leave patients navigating side effects, uncertainty and decisions about whether continuing feels worth it. I’m curious whether stopping lecanemab has changed the shivering at all yet, or whether it has persisted unchanged.