These results were greeted with enthusiasm by experts, who did not hesitate to welcome the entry into a "new era" for the management of Alzheimer's disease, thanks to several recent breakthroughs.

The clinical trial, which included 1,200 participants between the ages of 60 and 85 who had not yet reached an advanced stage of the disease, showed a 36 percent reduction in cognitive decline in patients treated with donanemab, according to a company statement.

The ability to perform everyday tasks, such as driving, conversing, having leisure or managing finances, was also measured. Over 18 months, participants who received the treatment had a 40% reduction in decline in their ability to perform these tasks.

Eli Lilly said it plans to file an application for authorization with the U.S. Food and Drug Administration (FDA) as early as this quarter, and worldwide "as soon as possible".

However, treatment can cause serious side effects, such as edema or cerebral hemorrhage. Three participants in the clinical trial died, according to the statement.

"When the full results are published" in a scientific journal, "we can begin to carefully evaluate the risks and benefits, and this will help decide whether donanemab should be routinely given to patients," commented Dr. Charles Marshall, of Queen Mary University of London.

Alzheimer's disease is a neurodegenerative disease that affects tens of millions of people worldwide, and for which there is no cure for it. Initially characterized by memory loss, patients gradually lose the ability to live normally.

New generation of treatments

"These results confirm that we are entering the era of Alzheimer's treatment," said Catherine Mummery of the National Hospital for Neurology and Neurosurgery in London. It will now be possible "to realistically hope to be able to treat and stabilize a person with Alzheimer's disease, with long-term management, rather than palliative and supportive care," she added.

"I believe this treatment has the potential to significantly improve the lives of patients and their families," said Dr. Marc Busche of University College London (UCL).

Research in the fight against Alzheimer's disease has stagnated for decades.

But two new treatments, developed by the Japanese pharmaceutical companies Eisai and the American Biogen, have recently been approved in the United States: Leqembi in January 2023 (whose active ingredient is called lecanemab), and before that Aduhelm (aducanumab molecule), in June 2021.

While the approval of Aduhelm has been controversial, with many experts criticizing the lack of evidence on its efficacy, lecanemab was the first to clearly demonstrate a reduction in cognitive decline (by 27%) in a clinical trial.

Eli Lilly's donanemab, if "approved alongside lecanemab", could "offer a choice of treatments to patients", welcomed Liz Coulthard, professor at the University of Bristol.

All of these new treatments target deposits of a protein called beta-amyloid. While the exact cause of Alzheimer's disease remains poorly understood, patients' brains have amyloid plaques, which form around their neurons and eventually destroy them.

Limited access

Access to these treatments, administered intravenously and very expensive, is the subject of debate in the United States.

The federal Medicare health coverage system, aimed at people over 65, had announced that it would reimburse them only if they were taken in clinical trials -- de facto limiting their access.

This condition was set because the FDA approved Aduhelm and Leqembi under an accelerated procedure, which requires less clinical data to be collected in order to allow a treatment for a serious condition to be brought to market more quickly.

"Medicare continues to stubbornly block access for people who could benefit from it," Maria Carrillo, chief scientist at the Alzheimer's Association, said in a statement Wednesday, calling for these access restrictions to be lifted.

Eli Lilly said Wednesday it wants to file for a "traditional" (not expedited) authorization, which could allow broader coverage by Medicare.

© 2023 AFP