By Deena Beasley
(Reuters) – Biogen Inc’s Alzheimer’s drug Aduhelm, approved by U.S. regulators last year for its ability to reduce amyloid brain plaques, also lowers levels of a second protein that accumulates in the brains of people with the disease, according to new data released by the company on Thursday.
Biogen said its Phase III studies found that Aduhelm significantly lowered blood levels of an abnormal form of the protein tau – another target of experimental Alzheimer’s drugs – that forms toxic tangles of nerve fibers associated with the mind-wasting disease.
The tau levels were correlated to changes in amyloid plaques and with slowing of cognitive and functional decline, the company said.
In one trial, tau levels in patients with early Alzheimer’s given the highest dose of Aduhelm fell 13%, compared with an increase of 8% for placebo patients. In the second trial, high-dose patients saw tau levels decrease 16%, while levels in the placebo group rose 9%.
“We now have robust and concordant data that Aduhelm has effect on two core defining pathologies of Alzheimer’s disease,” Biogen research chief Alfred Sandrock said in a statement.
The findings were presented on Thursday at the Clinical Trials on Alzheimer’s Disease conference held virtually and in Boston.
Since brain changes associated with Alzheimer’s, including amyloid and tau deposits, begin years before cognitive decline can be identified, drug development in recent years has focused on early treatment that can interfere with underlying changes believed to lead to the disease.
Only one of Biogen’s two pivotal trials showed Aduhelm can slow the rate of cognitive decline for Alzheimer’s patients. Many experts have questioned the Food and Drug Administration’s rationale for approving the drug without more definitive proof of benefit.
The FDA has defended its decision by saying there is clear evidence that Aduhelm removes amyloid from the brains of people with Alzheimer’s, arguing that the effect is reasonably likely to predict a clinical benefit to patients.
Some members of an advisory panel to the FDA resigned in protest and several prominent treatment centers have publicly said they will not offer Aduhelm to patients.
The new data shows that when the drug clears amyloid plaques it then impacts markers of neurologic degeneration, leading to improvements in clinical outcomes, Biogen Chief Medical Officer Maha Radhakrishnan said in an interview.
Early sales of Aduhelm, priced at $56,000-a-year, have been slow. Third-quarter sales of $300,000 were far below the nearly $11 million Wall Street had expected. Medicare, the government’s health plan for people over age 65, expects to issue a draft decision on its reimbursement policy – which will apply to all plaque-reducing agents – in January, with a final policy due in April.
In 2020, an estimated 5.8 million Americans aged 65 years or older had Alzheimer’s disease, according to the U.S. Centers for Disease Control and Prevention. This number is projected to nearly triple to 14 million people by 2060.
(Reporting By Deena Beasley; Editing by Bill Berkrot)
