An investigational drug showing promise in reducing cognitive decline in early Alzheimer’s disease is being hailed as having potential to “change the course” of the disease.
Initial results of a Phase 3 clinical trial of lecanemab announced late Tuesday are being hailed by some as a “major milestone” in Alzheimer’s disease treatments.
Japanese drugmaker Eisai and US biotechnology company Biogen on Tuesday announced the positive results from the Clarity AD clinical trial of lecanemab. It is an investigational anti-amyloid beta antibody in the treatment of mild cognitive impairment due to Alzheimer’s disease and mild Alzhemier’s disease. Results will be presented Nov. 29 at the Clinical Trials on Alzheimer’s Congress.
“These are the most encouraging results in clinical trials treating the underlying causes of Alzheimer’s to date,” Alzheimer’s Association President Joanne Pike, DrPH, said in announcing the results. “These results indicate lecanamab may give people more time at or near their full abilities to participate in daily life, remain independent and make future healthcare decisions.”
More than 6 million Americans are living with Alzheimer’s disease, according to the Alzheimer’s Association. Alzheimer’s and other dementias will cost the national $321 billion this year alone, and by 2050, those costs could increase to almost $1 trillion.
Biogen CEO Michel Vounatsos said that the study shows that removing aggregated amyloid beta in the brain is associated with a slowing of early stage disease.
“Today’s announcement gives patients and their families hope that lecanemab, if approved, can potentially slow the progression of Alzheimer’s disease, and provide a clinically meaningful impact on cognition and function,” he said. “Importantly, the study showed that removal of aggregate amyloid beta in the brain is associated with a slowing of disease in patients at the early stage of the disease.”
The study involved 1,795 individuals in whom early Alzheimer’s disease had been diagnosed. The treatment group received a 10 milligram bi-weekly intravenous dose of lecanemab over 18 months.
The drug slowed progress of the disease by 27% compared with a placebo. Eisai said that the study’s results prove the theory that removing amyloid plaques — clumps of protein in the brain — can delay the advancement of disease.
Brain swelling or brain bleeding was experienced by 21.3% of clinical trial participants. Less than 3% of those participants showed symptoms, according to the companies.
The study used the Clinical Dementia Rating sum of boxes (CDR-SB), which measures six cognitive domains including memory, orientation, judgment and problem solving, community affairs, home and hobbies, and personal care.
Another significant aspect of the study is that roughly 25% of participants were Hispanic or Black, making it one of the more diverse populations enrolled in an Alzheimer’s clinical trial, according to the companies.
Paving the way for innovation
“Eisai believes these findings will create new horizons in the diagnosis and treatment of Alzheimer’s disease, as well as further activate innovation for new treatment options,” Eisai CEO Haruo Naito said in a statement.
UC Irvine Institute for Memory Impairments and Neurological Disorders called the announced “exciting” but cautioned that more information is needed on the data, the trial participants and side effects.
The FDA granted priority review for lecanemab in July under the accelerated approval pathway. A decision is expected in January. Eaisai aims to file for traditional approval of the drug in the United States and said it will submit marketing authorization applications in Japan and Europe by the end of the first quarter of 2023.
Lecanema also is being tested for its potential benefits even before Alzheimer’s symptoms begin in the AHEAD study. That study will assess whether the drug can delay or prevent the onset of symptoms in people at increased risk. Participants are individuals aged 55 to 80 years who are cognitively unimpaired but who show amyloid PET scans indicate the amyloid accumulation in the brain.
In 2021, lecanemab was selected for the Tau NexGen clinical study for Dominantly Inherited Alzheimer’s disease, or DIAD, as a background anti-amyloid treatment when exploring combination therapies with anti-tau treatments. The study is being conducted by Dominantly Inherited Alzheimer Network Trials Unit, or DIAN-TU, led by the Washington University School of Medicine in St. Louis.