The Current

Are scientists asking the right questions when it comes to testing Alzheimer's drugs?

The cancellation of a clinical trial for a potential Alzhemier's drug is raising questions over the feasibility of the "amyloid hypothesis" — a specific theory for a cure that scientists have been pursuing for years. Do scientists need to start exploring new avenues?

Pharmaceutical companies pulled the plug on clinical testing of one treatment for disease last week

A woman suffering from Alzheimer's holds the hand of a relative in a retirement house in France. Last week, companies Biogen and Eisai pulled the plug on clinical trials for a drug that held hope of slowing cognitive decline in patients with the disease. (SEBASTIEN BOZON/AFP/Getty Images)

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The cancellation of two promising clinical trials for a potential Alzheimer's drug is raising concern among some in the medical community that scientists are too focused on the "amyloid hypothesis" in the fight to cure the disease.

Last week, pharmaceutical companies Biogen and Eisai announced they were pulling the plug on testing a drug called aducanumab, which was designed to slow cognitive decline in Alzheimer's patients.

The clinical trials were aimed at removing the amyloid-beta, a protein linked to Alzheimer's disease, from the brain. Researchers believed getting rid of it could help treat the disease, a theory known as the amyloid hypothesis, said Simone Fishburn, vice-president and executive director of BioCentury, which does research and analysis about the biopharmaceutical industry.

Fishburn said there have been many clinical trials focused on the protein — trials involving thousands of patients and millions of dollars — however, "it really has yet to bear fruit," she told The Current's guest host Piya Chattopadhyay.

Science advances by failures.- Simone  Fishburn , vice-president and executive director of BioCentury

Scientists need to examine whether they're asking questions to truly get the answers, or whether they're doing it "just to double down on something that they've invested so much time and effort in," she said.

"Science advances by failures."

'Cocktail' cure may be the answer

Dr. Sandra Black, a cognitive and stroke neurologist in Toronto, says there could be a more balanced approach in the research for drugs to tackle Alzheimer's disease.

"Scientists are supposed to be objective, but they get very attached to their own hypotheses," she explained.

Black predicts there won't be a single cure, but rather a "cocktail, just like in cancer."

To discuss the clinical trials and treating Alzheimer's, Chattopadhyay spoke to:

  • Simone Fishburn, vice-president and executive director of BioCentury, which does research and analysis about the biopharmaceutical industry.
  • Dr. Sandra Black, a cognitive and stroke neurologist whose research includes work on amyloids. She directs the Toronto Dementia Research Alliance, and the Hurvitz Brain Sciences Research Program at Sunnybrook Health Sciences Centre.
  • Dr. Saskia Sivananthan, a neuroscientist and chief of research at the Alzheimer Society of Canada.

Click 'listen' near the top of this page to hear the full conversation.

Produced by Alison Masemann.


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