US approves first new Alzheimer's drug in two decades

US government health officials have approved the first new drug for Alzheimer’s disease in nearly 20 years, disregarding warnings from independent advisers that the much-debated treatment hasn’t been shown to help slow the brain-destroying disease.

The Food and Drug Administration said it granted approval to the drug developed by Biogen for patients with Alzheimer's disease.

It’s the only drug that US regulators have said can likely treat the underlying disease, rather than manage symptoms like anxiety and insomnia.

The decision, which could impact millions of older Americans and their families, is certain to spark disagreements among physicians, medical researchers and patient groups. 

It also has far-reaching implications for the standards used to evaluate experimental therapies, including those that show only incremental benefits.

The new drug, which Biogen developed with Japan’s Eisai Co, did not reverse mental decline, only slowing it in one study.

Named Aduhelm, the medication is given as an infusion every four weeks.

READ MORE: Alzheimer's breakthrough drug gives hope

'Any price is too high'

The FDA's top drug regulator acknowledged in a statement that “residual uncertainties” surround the drug, but said Aduhelm's ability to reduce harmful clumps of plaque in the brain “is expected” to help slow dementia.

Under terms of the approval, the FDA is requiring the drugmaker to conduct a follow-up study to confirm benefits for patients. 

If the study fails to show effectiveness, the FDA could pull the drug from the market, though the agency rarely does so.

Biogen did not immediately disclose the price, though analysts have estimated the drug could cost between $30,000 and $50,000 for a year's worth of treatment.

A preliminary analysis by one group found that the drug would need to be priced $2,500 to $8,300 per year to be a good value based on the “small overall health gains” suggested by company studies. 

The non-profit Institute for Clinical and Economic Review added that “any price is too high” if the drug’s benefit isn’t confirmed in follow-up studies.

Nearly 6 million people in the US and many more worldwide have Alzheimer’s, which gradually attacks areas of the brain needed for memory, reasoning, communication and basic daily tasks.

In the final stages of the disease, those afflicted lose the ability to swallow. 

READ MORE: Alzheimer's treatment almost within reach

A global burden

The global burden of the disease, the most common cause of dementia, is only expected to grow as millions more Baby Boomers progress further into their 60s and 70s.

Aducanumab (pronounced “add-yoo-CAN-yoo-mab”) helps clear a protein linked to Alzheimer's, called beta-amyloid, from the brain. 

Other experimental drugs have done that before but they made no difference in patients’ ability to think, care for themselves or live independently.

The FDA’s green light is likely to revive investments in similar therapies previously shelved by drugmakers.

The new medicine is made from living cells that will have to be given via infusion at a doctor’s office or hospital.

Researchers don’t fully understand what causes Alzheimer’s but there’s broad agreement that the brain plaque targeted by aducanumab is just one factor. 

Growing evidence suggests family history, education and chronic conditions like diabetes and heart disease may all play a role.

“This is just one piece of the puzzle and I think all these other options need to be explored and amplified,” said Dr Ronald Petersen, a Mayo Clinic dementia specialist who has consulted for Biogen and other drugmakers.

Many experts have warned that green lighting the drug could set a dangerous precedent, opening the door to treatments of questionable benefit.

The approval came despite a scathing assessment in November by the FDA’s outside panel of neurological experts. 

The group voted “no” to a series of questions on whether reanalysed data from a single study submitted by Biogen showed that the drug was effective.

Cambridge, Massachusetts-Biogen halted two studies of the drug in 2019 after disappointing results suggested aducanumab would not meet its goal of slowing mental and functional decline in Alzheimer's patients.

READ MORE: Blood test might show early signs of Alzheimer’s disease