New data suggests novel mAb could delay progression of early Alzheimer’s

Eli Lilly and Company’s TRAILBLAZER-ALZ 2 study has shown donanemab enabled nearly half of participants at earlier stage of Alzheimer’s to experience no clinical progression at one year, according to full results from the Phase III trial.

The data was shared at the 2023 Alzheimer’s Association International Conference (AAIC) and published in the Journal of the American Medical Association (JAMA). Additional subpopulation analyses presented revealed that participants at the earliest stage of the disease had a 60 percent slowing of decline compared to placebo.

Publication of this data follows on from a response letter issued by the US Food and Drug Administration (FDA) in January this year, for Eli Lilly and Company’s accelerated approval submission of donanemab for early Alzheimer’s.

Data from the landmark Alzheimer’s study

“This is the first Phase III study of a disease-modifying therapy to replicate the positive clinical results observed in a previous study,” stated Anne White, Executive Vice President of the Big Pharma firm Eli Lilly and Company and President of Lilly Neuroscience.

“It is important to stress that donanemab does not improve symptoms but slows down deterioration,” Professor Paresh Malhotra, Head, Division of Neurology, Imperial College London, and Consultant Neurologist, Imperial College Healthcare NHS Trust emphasised.

Additional data presented at AAIC confirmed that regardless of baseline clinical or pathological stage of Alzheimer’s, donanemab treatment provided cognitive and functional benefits relative to placebo.

The overall treatment effect of the monoclonal antibody (mAb) donanemab continued to grow throughout the trial, with the largest differences versus placebo seen at 18 months.

Among all participants, treatment with donanemab reduced amyloid plaque on average by 84 percent at 18 months, compared with a one percent decrease for participants on placebo.

Clinical trial participants were able to stop taking donanemab once they achieved pre-defined criteria of amyloid plaque clearance. Approximately half of participants met this threshold at 12 months. Around about seven of every ten participants reached this limit at 18 months.

Those given donanemab also had a 39 percent lower risk of progressing to the next clinical stage of Alzheimer’s over the 18-month trial. This delay in progression meant that, on average, these participants had an additional 7.5 months before they reached the same level of cognitive and functional decline on Clinical Dementia Rating-Sum of Boxes (CDR-SB) rating compared to those on placebo.

Regulatory approval of donanemab

White added: “If approved, we believe donanemab can provide clinically meaningful benefits for people with this disease and the possibility of completing their course of treatment as early as six months once their amyloid plaque is cleared.”

Submission to the US FDA for traditional approval was completed last quarter. Regulatory action is expected by year end. Eli Lily is currently submitting to other global regulators.