US regulator delays decision on Eli Lilly’s Alzheimer’s drug donanemab

The US drug regulator has delayed an approval decision on Eli Lilly’s promising Alzheimer’s disease drug, which was expected to be greenlit this month.

A decision from the US Food and Drug Administration on Eli Lilly’s donanemab drug was originally due by the end of the first quarter but the breakthrough medicine will now be subject to a further review by an advisory committee of independent experts.

“The FDA has informed Lilly it wants to further understand topics related to evaluating the safety and efficacy of donanemab, including the safety results in donanemab-treated patients and the efficacy implications of the unique trial design,” the Indianapolis-based group said on Friday.

The FDA, which declined to comment, is expected to take several months to convene the panel of experts, according to a person close to Eli Lilly. This would result in FDA action being delayed beyond the first quarter, the company said in its statement.

Finding an effective treatment for Alzheimer’s has proved fiendishly difficult for drug companies, and previous regulatory decisions in the field have stirred controversy. In January, Biogen relinquished ownership rights to its first-of-its-kind Alzheimer’s drug Aduhelm after a years-long saga over the accelerated approval process led to criticism from two congressional committees and resignations from three independent experts at the FDA.

Donanemab — which analysts project will reach so-called blockbuster status of $1bn in sales by 2026 — was shown to slow cognitive decline in a study of 1,736 patients with early-stage Alzheimer’s. Nearly half of participants who took the drug had no clinical progression after a year, compared with 29 per cent for the placebo drug.

“It was unexpected to learn the FDA will convene an advisory committee at this stage in the review process,” said Anne White, president of Lilly Neuroscience. But she said the drugmaker was “confident in donanemab’s potential to offer very meaningful benefits to people with early symptomatic Alzheimer’s disease”.

Similar to other Alzheimer’s treatments, donanemab works by targeting and removing amyloid, a plaque that forms on patient’s brains and is linked to the cognitive decline associated with Alzheimer’s.

Leqembi, an Alzheimer’s drug produced by Biogen and Japan-based pharma group Eisai, received approval from the FDA in July last year. But its rollout has been slower than expected with only 2,000 US patients accessing the treatment by January 26, according to Eisai.

Donanemab requires monthly infusions that take several hours and multiple MRI scans a year to check for side effects, in particular amyloid-related imaging abnormalities (Aria) which can lead to brain swelling and, in extreme cases, be life-threatening. Leqembi requires fortnightly infusions.

Eli Lilly noted in a statement that the approval process for both Aduhelm and Leqembi, which are also amyloid plaque-targeting treatments, required similar additional advisory committee meetings. Patients on the donanemab study had more advanced Alzheimer’s than patients on similar studies, Eli Lilly said.