Alzheimer's Drugs May Not Reduce Dementia Deaths, Cambridge Scientists Warn

Strategic Insights -

Cambridge scientists have warned that Alzheimer's treatments, which claim to slow down the progression of the disease, may not be able to reduce the number of deaths from dementia. The treatments, lecanemab and donanemab, have been hailed as breakthroughs in the fight against Alzheimer's, but critics argue that the benefits do not outweigh the substantial financial costs and high risk of severe side effects.

Key Takeaways:

  • The two treatments, lecanemab and donanemab, work by clearing out amyloid in the brain, but may not be able to reduce dementia deaths due to their small impact size.
  • Data from trials show a 27% and 35% slowing of cognitive decline in people with early-stage Alzheimer's, but the impact is so small it would not be recognizable by a doctor or the patient.
  • The drugs are expensive, costing around £20,000 a year, and are given in hospital as an intravenous drip.
  • The high risk of side effects, including brain shrinkage and bleeds, makes the potential rollout of the treatments "extremely challenging" for even the best-funded healthcare systems.
  • Only two percent of eligible people with early signs of Alzheimer's will be able to receive the drug due to the need for specialist PET brain scans.
  • The Cambridge scientists warn that the price of the drugs, the demands on the patient and health service, and the high risk of side effects make the treatments "a part of the puzzle" rather than a solution to the problem of dementia.
  • There are currently 164 active clinical trials for Alzheimer's disease, and more treatments are expected to be submitted for regulatory approval in the future.

Statistics:

  • 27% slowing of cognitive decline in people with early-stage Alzheimer's on lecanemab (Source: Eisai trial data)
  • 35% slowing of cognitive decline in people with early-stage Alzheimer's on donanemab (Source: Eli Lilly trial data)
  • £20,000 per year cost of lecanemab and donanemab (Source: Cambridge scientists)
  • 2% of eligible people with early signs of Alzheimer's will be able to receive the drug due to the need for specialist PET brain scans (Source: Cambridge scientists)
  • 164 active clinical trials for Alzheimer's disease (Source: Alzheimer's Society)

Sources:

  • Cambridge scientists, University of Cambridge perspective article in Alzheimer's and Dementia journal
  • Eisai trial data on lecanemab
  • Eli Lilly trial data on donanemab
  • Alzheimer's Society
  • Medicines and Healthcare products Regulatory Agency (MHRA)
  • National Institute for Health and Care Excellence (Nice)