Alzheimer's drug TGA approval "momentous" — but is health care ready?

On 22 May, following news that the Therapeutic Goods Administration (TGA) had approved the use of Kisunla (donanemab) in Australia — the first drug registered in Australia that has been proven to significantly slow the progression of Alzheimer’s disease — Professor Christopher Rowe MD FRACP, Director of Australian Dementia Network (ADNeT), said: “Today is a momentous day in the treatment of the most common form of dementia. We must now ensure our health system is ready with the diagnostic tools and expert staff to bring these new treatments to patients.”

The TGA approval comes almost 12 months after donanemab was approved in the United States — with subsequent approvals in Japan, China and Great Britain — and grants Australians access to a therapy shown to slow decline by one-third in persons with Alzheimer’s disease. With dementia being the largest disease burden in older Australians, progressively erasing memories, altering personalities and diminishing daily capabilities — leading to severe incapacity and death over an average period of eight years from diagnosis — and Alzheimer’s disease being the most common form of dementia, this news offers much hope.

Donanemab’s potential is especially significant given that the number of Australians living with dementia is expected to increase to an estimated 812,500 by 2054 — from around 433,000 currently. But it’s a drug that needs to be given at the first signs of the disease and needs to be closely monitored to avoid serious side effects, as ADNeT — a partnership of leading Australian dementia researchers from across 21 universities and research institutions — explains.

“Currently there is an average three-year delay between first signs and getting a diagnosis of AD [Alzheimer’s disease] and waiting times to see dementia specialists in many areas are over a year,” ADNeT said in a statement following news of the approval. “Monthly infusions and frequent brain imaging is required when on treatment. To meet the expected demand for this treatment the health system will need to rapidly change.” Given that the drug gives greatest benefits to patients when administered soon after a timely diagnosis, ADNeT is calling for a new, more streamlined diagnosis approach.

Also needed, ADNeT says, is investment in GP and specialist education, expansion of Memory Clinics and infusion centres, provision of patient support staff, and access to the new Alzheimer’s disease blood tests, to triage those suitable for treatment. In short, patients with a recent diagnosis of early Alzheimer’s disease stand to benefit greatly from the therapy, but proper diagnostic tools and support to ensure patients can access this treatment in a timely and beneficial manner is needed.

“The day has finally arrived when Australians with early Alzheimer’s disease can access a new treatment that for the first time is proven to slow the disease,” Rowe said. “This drug buys valuable time, slowing the rate of progression towards severe dementia by one-third. We need broad application of diagnostic blood tests around Australia to ensure GPs can diagnose Alzheimer’s in a timely and accurate manner and open the possibility of their patients receiving these treatments.”

While previous regulatory decisions have raised concerns about potential side effects from donanemab in earlier trials, Rowe said that the risk of serious damage from the drug is about one in 200, when given carefully and to the right patients. “I am sure that many patients would gladly accept this risk,” Rowe said, noting that strict monitoring protocols need to be in place, and close monitoring with MRI scans is required in the first six months of treatment, when these problems are most likely to occur.

Image credit: iStock.com/Jacob Wackerhausen