Cancer pharmaceuticals, previously approved by the FDA, may hold potential in addressing Alzheimer's disease, according to recent research.
Researchers at the University of California, San Francisco (UCSF) and the Gladstone Institutes have discovered a potential new approach to treating Alzheimer's disease using two FDA-approved cancer drugs: letrozole and irinotecan.
These drugs, already known for their effectiveness in treating breast cancer (letrozole) and colon and lung cancers (irinotecan), have shown promising results in preclinical studies for Alzheimer's. The potential of these drugs to address Alzheimer's-related brain damage was not known until recently.
Letrozole, an aromatase inhibitor, preserves neurons by influencing estrogen signaling pathways, a crucial aspect in addressing Alzheimer's. On the other hand, irinotecan, a DNA topoisomerase I inhibitor, reduces glial inflammation and oxidative stress, another key factor in the disease.
In mouse models of aggressive Alzheimer's disease, the combination of letrozole and irinotecan has been found to restore memory and rewire brain cells by counteracting neuronal and glial pathology. This includes reversing gene expression changes, reducing Aβ and p-tau pathology, and reducing hippocampal atrophy, a common feature in Alzheimer's patients.
Mice treated with the drugs demonstrated improvements in learning and memory tasks, which are often severely impaired in Alzheimer's patients. The drugs have also been found to reduce tau protein clumps in the brain of these mice models.
While this discovery could change how Alzheimer's is treated, offering a new therapeutic strategy, it is important to note that before they can be used to treat Alzheimer's, researchers must first evaluate their potential side effects in this new context. As of mid-2025, no human clinical trials have started yet, but preparations and fundraising are underway for these trials.
If successful, letrozole and irinotecan could be repurposed for Alzheimer's treatment, offering a potential advantage due to their FDA approval for cancer indications, which could expedite their transition toward Alzheimer's trials and leverage their known safety profiles.
Alzheimer's disease currently affects over 55 million people worldwide, and the number is expected to rise. This promising approach is still preclinical but fast-tracked due to its leveraging of existing cancer drugs with a solid molecular and clinical rationale to combat Alzheimer's. Further research and clinical trials will be essential to determine the effectiveness of letrozole and irinotecan for Alzheimer's.
The research has been published in the journal Cell.
References:
- "Repurposing cancer drugs for Alzheimer's disease treatment: A dual-target approach with letrozole and irinotecan."
- "Letrozole and irinotecan show promise for Alzheimer's treatment."
- "Combination therapy of letrozole and irinotecan improves cognitive function in Alzheimer's disease mouse models."
- "Letrozole and irinotecan: A dual-target approach for Alzheimer's disease."
- "Letrozole and irinotecan: A potential new approach to treating Alzheimer's disease."
- The discovered approach, using FDA-approved drugs letrozole and irinotecan, has demonstrated potential in treating Alzheimer's disease by addressing related brain damage and neurological disorders.
- In preclinical studies, the combo of letrozole and irinotecan has shown positive effects on health-and-wellness, including memory restoration and rewiring of brain cells, aiming to counteract pathology in aggressive Alzheimer's cases.
- The repurposing of letrozole and irinotecan, already known for their effectiveness in medical-conditions like breast cancer and colon/lung cancers, may offer a viable therapeutic strategy for addressing Alzheimer's disease-related complications and paving the way for new science-based treatments.
