Eli Lilly's highly anticipated Alzheimer's drug has been held back for further review by regulators

Eli Lilly, a US pharmaceutical giant, announced on Friday that its highly anticipated Alzheimer's drug, Donanemab, has been delayed for further review by regulators, delivering a setback to patients grappling with the debilitating brain disorder.

While Donanemab demonstrated the ability to slow cognitive decline in the early stages of the disease during a clinical trial, there was a notable incidence of side effects, including fatalities.

In a statement, the Food and Drug Administration (FDA) informed Lilly that it intends to delve deeper into issues related to evaluating the drug's safety and efficacy. Consequently, a new meeting of experts will be convened, although a firm date has not been provided. As a result, the anticipated FDA action on Donanemab, initially expected in the first quarter of 2024, will be delayed.

"We are confident in Donanemab's potential to offer very meaningful benefits to people with early symptomatic Alzheimer's disease," remarked Anne White, the company's executive vice president. She noted that the FDA's decision for a new meeting was unexpected but affirmed their commitment to collaborate with the FDA and stakeholders to address all queries.

Donanemab functions as an intravenously injected antibody targeting the buildup of beta-amyloid, a protein prevalent in the brains of Alzheimer's patients.

Another anti-amyloid therapy, Leqembi, developed by Eisai of Japan and Biogen of Massachusetts, received full FDA approval last July and is now accessible through government-run health insurance for the elderly, known as Medicare.

While a study published in the Journal of the American Medical Association last year demonstrated that Donanemab slowed cognitive and functional decline in patients with early symptoms of Alzheimer's, serious adverse events, including brain bleeds, were observed in a significant percentage of patients receiving the drug.

Professor Robert Howard, a renowned expert in old age psychiatry at University College London, characterized the delay in granting US licensure as a significant setback for Lilly, citing concerns about the drug's adverse effects compared to other approved treatments.

Amidst the evolving landscape of Alzheimer's drug development, safety considerations remain paramount. The US Alzheimer's Association emphasized the importance of swift action in the FDA's review process to benefit individuals potentially eligible for treatment.

The delay in Donanemab's approval comes after the withdrawal of the first FDA-approved Alzheimer's drug, Aduhelm, in January, underscoring the challenges in translating promising treatments into tangible benefits for patients grappling with this devastating disease.