What are the risks of microhemorrhages with donanemab (anti-amyloid beta antibody) treatment?

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From the FDA Drug Label

5.1 Amyloid Related Imaging Abnormalities Monoclonal antibodies directed against aggregated forms of beta amyloid, including KISUNLA, can cause amyloid related imaging abnormalities (ARIA), characterized as ARIA with edema (ARIA-E), which can be observed on MRI as brain edema or sulcal effusions, and ARIA with hemosiderin deposition (ARIA-H), which includes microhemorrhage and superficial siderosis ARIA-H was observed in 31% (263/853) of patients treated with KISUNLA compared with 13% (111/874) of patients on placebo.

The risk of microhemorrhages with donanemab treatment is increased, with ARIA-H, which includes microhemorrhage, observed in 31% of patients treated with donanemab compared to 13% of patients on placebo 1.

  • Key points:
    • ARIA-H, which includes microhemorrhage, is a risk associated with donanemab treatment.
    • The incidence of ARIA-H is higher in patients treated with donanemab compared to placebo.
    • Microhemorrhages can occur as part of ARIA-H, and the risk is increased in patients treated with donanemab.

From the Research

Donanemab treatment carries significant risks of microhemorrhages, with approximately 27.2% of patients developing microhemorrhages in clinical trials, as reported in the most recent study 2. The risk of microhemorrhages with donanemab treatment is a significant concern, particularly in patients with a history of cerebrovascular disease or those carrying the APOE4 gene. Some key points to consider when evaluating the risk of microhemorrhages with donanemab treatment include:

  • The frequency of microhemorrhages: approximately 27.2% of patients developed microhemorrhages in clinical trials, as reported in the most recent study 2.
  • The risk factors for microhemorrhages: patients carrying the APOE4 gene, particularly homozygotes, are at higher risk for microhemorrhages, with rates reaching up to 64% in some studies 2.
  • The symptoms of microhemorrhages: most microhemorrhages are asymptomatic, but approximately 6% of patients may experience symptoms, including headache, confusion, dizziness, visual disturbances, or rarely, more severe neurological deficits 2.
  • The monitoring requirements: regular MRI monitoring is required during treatment, typically at baseline and before the 5th, 7th, and 14th doses, to detect microhemorrhages early and prevent severe complications 2.
  • The management of microhemorrhages: if severe microhemorrhages develop, treatment interruption or discontinuation may be necessary, and patients should be informed about these risks before starting treatment 2.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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