LAST week the US Food and Drug Administration (FDA) approved a new treatment for Alzheimer’s, the first since 2003, and so far the only therapy that targets the fundamental pathophysiology of the disease. Aducanumab, manufactured by Biogen, of Cambridge, Massachusetts will be marketed as Aduhelm.
Alzheimer’s is an irreversible, progressive brain disorder that slowly destroys memory and cognitive skills. It is estimated to affect 6million in the US and 850,000 (or one in 14) in the UK.
While the specific causes of Alzheimer’s disease are not fully understood, a likely cause is sticky deposits in the brain of a protein called amyloid beta. Aduhelm promises to remove these in the early stages. It is not a cure but is reported to inhibit physical and cognitive deterioration.
Biogen estimates that more than 1.5million Americans might be eligible for treatment with aducanumab, which is priced at $56,000 a year per patient. The firm’s shares jumped more than 50 per cent to $434.52 after the approval.
However the drug is not without controversy. It went through the FDA’s ‘accelerated approval pathway’ which seeks to expedite the development of drugs that show potential to address an ‘unmet medical need’. Questions about the clinical evidence supporting claims of its effectiveness persist.
Three separate studies representing a total of only 3,482 patients were submitted. Some patients suffered potentially dangerous ‘non-symptomatic’ brain swelling, while others reported headaches, confusion, dizziness, vision changes, nausea, falls, diarrhoea, delirium and disorientation – a range of horrors you would not wish to inflict on anyone with dementia.
Three experts resigned from the FDA’s advisory committee after the agency approved the drug despite the almost unanimous opposition of panel members.
The FDA website acknowledges that clinical benefits data from the treatment trials were ‘complicated’ but declares that ‘there is substantial evidence that Aduhelm reduces amyloid beta plaques in the brain and that the reduction in these plaques is reasonably likely to predict important benefits to patients.’
Biogen is required to conduct a ‘post-approval trial to verify’ Aduhelm’s clinical benefits and the FDA assures people that it could be withdrawn from the market if it does not work as intended. This is a highly risky approach that seems to signal a move away from the precautionary principle that is supposed to underpin all public health developments in a free society.
It ignores the fact that the purpose of this tax-funded agency is to protect citizens from harm by ‘assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products’ before they are launched on to the market.
Public Citizen’s Health Research Group, established by Dr Sidney Wolfe and Ralph Nader in 1971, criticised the approval, saying it shows ‘reckless’ disregard for science and severely damages the agency’s credibility.
In a statement, the group said the approval was based on seriously flawed analyses of two identical phase 3 trials that were stopped at the halfway point because a preliminary review of the data found that the trials, if continued to completion, were unlikely to show the drug benefited Alzheimer’s patients. One trial showed no benefit, and the other suggested possible minimal benefit at a high dose: ‘This approval could raise false hope in patients and potentially bankrupt the Medicare program because of the drug’s projected exorbitant price.’
Despite the risks, many sufferers will reach for this new drug as a drowning man will clutch at a straw.