How to manage microhemorrhages in patients on Leqembi (lecanemab)?

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From the FDA Drug Label

The baseline presence of at least 2 microhemorrhages or the presence of at least 1 area of superficial siderosis on MRI, which may be suggestive of CAA, have been identified as risk factors for ARIA The maximum radiographic severity of ARIA-H microhemorrhage in patients treated with LEQEMBI was mild in 9% (79/898), moderate in 2% (19/898), and severe in 3% (28/898) of patients ARIA-H The recommendations for dosing interruptions for patients with ARIA-H are provided in Table 2 In patients who develop intracerebral hemorrhage greater than 1 cm in diameter during treatment with LEQEMBI, suspend dosing until MRI demonstrates radiographic stabilization and symptoms, if present, resolve

Management of Microhemorrhages with Leqembi:

  • Dosing Interruptions: The decision to interrupt dosing in patients with microhemorrhages (ARIA-H) depends on the radiographic severity and clinical symptom severity.
  • Mild ARIA-H: May continue dosing.
  • Moderate or Severe ARIA-H: Suspend dosing until MRI demonstrates radiographic stabilization and symptoms, if present, resolve.
  • Intracerebral Hemorrhage: Suspend dosing until MRI demonstrates radiographic stabilization and symptoms, if present, resolve. Use clinical judgment in considering whether to continue treatment or permanently discontinue LEQEMBI.
  • Monitoring: Baseline brain MRI and periodic monitoring with MRI are recommended. Enhanced clinical vigilance for ARIA is recommended during the first 14 weeks of treatment with LEQEMBI. 1 1

From the Research

Managing microhemorrhages in patients on Leqembi (lecanemab) requires careful monitoring and risk assessment, with a recommendation to temporarily discontinue the medication and obtain MRI imaging to assess the extent of bleeding if microhemorrhages occur. For patients who develop microhemorrhages while on Leqembi, it is essential to evaluate them by a neurologist with expertise in amyloid-related imaging abnormalities (ARIA) 2. Before initiating Leqembi, all patients should undergo baseline MRI screening to detect pre-existing microhemorrhages, as those with more than four microhemorrhages or any hemorrhage >1 cm are at higher risk for ARIA. During treatment, follow the recommended MRI monitoring schedule: before the 5th, 7th, and 14th infusions.

Some key points to consider in managing microhemorrhages in patients on Leqembi include:

  • For asymptomatic ARIA-H (microhemorrhages) with fewer than 10 new microhemorrhages, Leqembi may be continued with close monitoring 3.
  • For symptomatic ARIA-H or cases with 10 or more new microhemorrhages, temporarily suspend treatment until symptoms resolve and radiographic stabilization occurs.
  • Concomitant use of anticoagulants or antiplatelet agents increases bleeding risk, so these medications should be used cautiously and only when clearly indicated.
  • Leqembi works by targeting amyloid plaques in cerebral blood vessels, which can temporarily increase vessel fragility and lead to microhemorrhages, particularly in patients with cerebral amyloid angiopathy 4.

It is also important to note that the risk of microhemorrhages is higher in certain populations, such as those with cerebral amyloid angiopathy, and that the use of anticoagulants or antiplatelet agents can increase this risk 5, 6. Therefore, careful consideration should be given to the potential risks and benefits of Leqembi treatment in these patients.

In terms of specific management strategies, the most recent and highest quality study 3 provides guidance on the management of microhemorrhages in patients on Leqembi, including the recommendation to temporarily discontinue treatment in cases of symptomatic ARIA-H or 10 or more new microhemorrhages. This study also highlights the importance of close monitoring and regular MRI imaging to detect and manage microhemorrhages early.

References

Research

Lecanemab: Appropriate Use Recommendations.

The journal of prevention of Alzheimer's disease, 2023

Research

Lecanemab (Leqembi) is not the right drug for patients with Alzheimer's disease.

Advances in clinical and experimental medicine : official organ Wroclaw Medical University, 2023

Research

Cerebral microhemorrhage.

Stroke, 2006

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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