FDA Approves Lilly's Alzheimer’s Drug

The U.S. Food and Drug Administration (FDA) has given the green light to a new Alzheimer's disease medication developed by Eli Lilly, called Kisunla. This approval follows the unanimous recommendation from a panel of independent experts. Kisunla aims to slow the progression of Alzheimer's by targeting and clearing amyloid, a toxic protein in the brain believed to be a primary cause of the disease. This newly approved drug joins two similar treatments on the market, Leqembi from Eisai and Biogen.

Kisunla is approved for use in patients who exhibit mild cognitive impairment or mild dementia due to Alzheimer's, provided they have confirmed amyloid pathology. This patient population is similar to those eligible for Leqembi. FDA reviewers had considered whether Kisunla treatment should be limited to patients with deposits of another brain protein, tau, which was a criterion in the drug's clinical trials.

A significant concern associated with Kisunla is the risk of ARIA (amyloid-related imaging abnormalities), which can cause brain swelling and bleeding. Although usually asymptomatic, ARIA can lead to serious complications. The drug’s labeling advises doctors to test for genetic profiles associated with higher ARIA rates. This safety warning aligns with that of Leqembi.

Eli Lilly has priced Kisunla at just under $700 per vial, translating to approximately $32,000 annually if treatment is continued for a year. Comparatively, Leqembi is priced at $26,500 annually. However, Kisunla's clinical trials allowed for treatment cessation if amyloid deposits were sufficiently cleared from the brain. This approach, noted in the FDA's labeling, might reduce the overall cost for patients who quickly reach minimal amyloid levels.

Howard Fillit, co-founder and chief science officer of the Alzheimer's Drug Discovery Foundation, expressed optimism about the potential to stop treatment once effectiveness is achieved, which could lessen financial and treatment burdens on patients.

Unlike Biogen's Aduhelm and Eisai’s Leqembi, which initially received accelerated approval, Kisunla has been granted full traditional approval. This distinction is crucial for reimbursement under the federal Medicare program, which covers the majority of Alzheimer's patients. Accelerated approval did not initially make Aduhelm or Leqembi eligible for such coverage, although Leqembi's approval status was later converted to full.

The approval of Kisunla comes after years of research focused on amyloid's role in Alzheimer's. Amyloid clumps into plaques that disrupt brain cell communication. Despite significant evidence supporting the amyloid hypothesis, previous drugs targeting amyloid failed to show benefits in clinical trials. Aduhelm, the first to reach patients, faced controversy over its efficacy and high cost, which deterred insurers. Leqembi, on the other hand, had more straightforward data backing its approval and has seen a gradual increase in sales following full FDA approval, though not to the extent anticipated by its developers.

There is ongoing debate among analysts about whether Leqembi or Kisunla will dominate the market. Data suggests that Leqembi might be safer, while Kisunla offers more convenience through less frequent dosing. However, no direct head-to-head trials have been conducted, complicating direct comparisons.

Expectations are high for Kisunla to become a major revenue generator for Eli Lilly, supplementing the company's successful diabetes and obesity treatments. Analysts predict that Kisunla could reach nearly $5 billion in annual sales at its peak.

Both Kisunla and Leqembi are recommended for early-stage Alzheimer's patients, underscoring the importance of early diagnosis and intervention. Joanne Pike, CEO of the Alzheimer’s Association, emphasized the necessity for equitable access to these treatments and the preparedness of healthcare systems to support eligible patients.