Posted July 3, 2024

On July 2, the FDA approved donanemab for the treatment of early symptomatic Alzheimer’s disease. Donanemab will be sold under the brand name Kisunla™ and will be delivered via once-monthly IV infusion.  The annual drug cost of Kisunla alone – not including provider or administration costs – is set at $32,000, but physicians can consider whether to halt treatment once an amyloid PET scan indicates the patient’s brain amyloid level is sufficiently cleared; in the clinical trial, 69% of patients were able to end treatment by 18 months.

The field expected that donanemab would be approved but some anticipated that the label, which guides physician prescription decision making, would narrowly define eligibility based on pathology and/or the absence of risk factors that increase potential side effects. However, the FDA label does not identify any comorbidities that should preclude treatment with Kisunla, but does indicate physicians should be cautious if a patient has risk factors for intracerebral hemorrhage such as pretreatment microhemorrhages or extensive white matter hyperintensities, use of anticoagulant (blood thinning) therapies, or MRI findings suggestive of cerebral amyloid angiopathy.

The FDA label for Kisunla recommends genetic testing to determine APOE4 status due to the higher risk of serious side effects observed in people who carry two copies of APOE4. The label directs physicians to confirm the presence of amyloid pathology prior to prescribing Kisunla but does not recommend or require that the presence of tau pathology be established.  Four MRIs spaced out over the course of the earliest treatment months are indicated to assess the patient for the brain swelling, lesions, and bleeding side effects that are for most people asymptomatic but that can be in rare cases catastrophic. All of this testing will incur costs in addition to those of the drug and its administration.  For most eligible people, Medicare will cover some but not all of these costs.

The approval of Kisunla comes one year after the approval by the FDA of another treatment for Alzheimer’s disease, Leqembi. In contrast to Kisunla, a year’s supply of Leqembi currently costs $28,000, infusions are every two weeks, and there are no validated criteria for when treatment can be stopped. Read more about Leqembi here https://curealz.org/news-and-events/fda-awards-full-approval-for-leqembi/

Read more about the review of donanemab here https://curealz.org/news-and-events/advisory-committee-to-fda-recommends-approval-of-alzheimers-drug-donanemab/