Alzheimer's Treatment: New Clinical Trials Offer Hope, But Expert Skepticism Remains

Strategic Insights -

While the causes of Alzheimer's disease are not yet fully understood, researchers have a strong consensus that the buildup of beta amyloid is a key factor in its development. This understanding has led to the pursuit of treatments that target the amyloid protein, with two high-profile clinical trials presented at the Alzheimer's Association International Conference in Washington, D.C. offering promising results. Biogen's adumanucab and Eli Lilly's solanezumab were tested in separate trials, with Biogen's antibody showing a reduction in amyloid levels in the brain, but failing to show significant cognitive benefits. Eli Lilly's antibody, on the other hand, seemed to slow cognitive decline in a subset of patients with mild Alzheimer's, but did not measure amyloid decline directly. While these findings provide some evidence that targeting beta amyloid is a promising approach to Alzheimer's treatment, experts remain skeptical about the results, citing the small cognitive benefits and the fact that one trial didn't show any reduction in amyloid in people's brains.

Key Takeaways:

  • The failure of over 120 clinical trials over the past 20 years in developing an effective treatment for Alzheimer's disease highlights the complexity of the issue.
  • Two high-profile clinical trials, one by Biogen and the other by Eli Lilly, tested antibodies that target beta amyloid, a protein that forms sticky masses in the brains of people with Alzheimer's, and showed mixed results.
  • Biogen's antibody, adumanucab, reduced levels of amyloid in the brain but failed to show significant cognitive benefits in a follow-up trial, while Eli Lilly's antibody, solanezumab, seemed to slow cognitive decline in a subset of patients with mild Alzheimer's.
  • Despite the initial promise of the findings, experts remain skeptical due to the small cognitive benefits and the lack of direct evidence of reduced amyloid levels in the brain.
  • The American Association for the Advancement of Science notes that only a handful of approved treatments for Alzheimer's disease provide modest and temporary relief for symptoms, and none halt the disease's progress.
  • Biogen will launch a new, larger trial of adumanucab in 2019, while Eli Lilly is currently running a phase III trial of solanezumab slated to end in October 2016.

Statistics:

  • Over 120 clinical trials have failed in developing an effective treatment for Alzheimer's disease in the past 20 years.
  • Two-thirds of patients with Alzheimer's die within eight years of diagnosis.
  • The Amyloid Cascade Hypothesis suggests that beta amyloid contributes to neurodegeneration through oxidative stress, inflammation, and the aggregation of neurotoxic peptides.
  • The tau hypothesis proposes that tau protein aggregation is a key factor in Alzheimer's disease, particularly in its later stages.
  • Only a handful of approved treatments for Alzheimer's disease provide modest and temporary relief for symptoms, and none halt the disease's progress.

Sources:

  • American Association for the Advancement of Science
  • Biogen
  • Eli Lilly
  • Harvard University
  • University of Texas Medical Branch in Galveston, Texas