Ambroxol May Slow Cognitive Decline in Parkinson’s Disease Dementia
A recent clinical trial suggests that Ambroxol, a widely used cough medicine in Europe, might slow cognitive decline in individuals with Parkinson’s disease dementia (PDD). Over the course of a year, the study observed that the drug not only stabilized psychiatric symptoms but also appeared to protect against brain damage and showed potential cognitive improvements in participants at genetic risk.
Ambroxol works by enhancing the activity of an enzyme known as GCase, which is often insufficient in Parkinson’s patients and contributes to brain cell damage. Although it hasn’t been approved yet for use in North America, its safety profile and preliminary benefits make it a strong candidate for further investigation.
Key Findings:
- Stabilized Symptoms: Ambroxol prevented the psychiatric decline observed in the placebo group.
- Genetic Advantage: Improvements in cognition were noted among participants with GBA1 gene variants.
- Brain Safety: A biomarker indicating brain damage remained stable for those taking Ambroxol.
Dementia is a significant health issue, and effective, safe treatments to slow its progression are lacking.
Research conducted at Lawson Research Institute, part of St. Joseph’s Health Care London, aimed to see if Ambroxol could impact dementia in Parkinson’s disease patients. The trial, published in the journal JAMA Neurology, included 55 participants and focused on changes in memory, psychiatric symptoms, and GFAP levels—a blood marker associated with brain damage.
Parkinson’s disease dementia often results in memory loss, confusion, hallucinations, and mood disturbances. It’s reported that nearly half of Parkinson’s patients develop dementia within a decade, significantly affecting not just the patients, but also their families and the healthcare system.
Leading the research, Dr. Stephen Pasternak emphasized the goal of altering the trajectory of Parkinson’s dementia. He noted that this initial trial brings hope and lays the groundwork for larger studies.
Among the findings:
- Ambroxol was safe, well-tolerated, and achieved therapeutic levels in the brain.
- Participants receiving the placebo experienced worsening psychiatric symptoms, while those on Ambroxol maintained stability.
- Patients with high-risk GBA1 gene variants demonstrated enhanced cognitive function with Ambroxol.
- The GFAP marker, indicating brain cell damage, increased for the placebo group but stabilized in the Ambroxol group, hinting at possible brain protection.
Although Ambroxol is commonly approved in Europe for respiratory issues and has a solid safety history—including use during pregnancy—it remains unapproved in Canada and the U.S.
Dr. Pasternak remarked that current Parkinson’s therapies focus on symptoms rather than addressing the disease itself. He highlighted the potential of Ambroxol to help protect brain function, especially for those genetically predisposed. This could mark a valuable new treatment path where options are currently limited.
Ambroxol supports the GCase enzyme, which tends to be deficient in Parkinson’s patients. When this enzyme fails to function properly, it can lead to the buildup of waste in brain cells and subsequent damage.
Pasternak first encountered Ambroxol during a fellowship at The Hospital for Sick Children in Toronto, where it was recognized as a treatment for Gaucher disease—a rare genetic disorder. He’s now applying that research to investigate whether boosting GCase with Ambroxol can offer brain protection in Parkinson’s-related conditions.
This research is crucial, as Parkinson’s dementia profoundly impacts patients and their families. “If a drug like Ambroxol can help, it might offer real hope and enhance quality of life,” Pasternak said.
Funded by the Weston Foundation, this study marks an essential step towards discovering new treatments for Parkinson’s and other cognitive disorders, such as dementia with Lewy bodies. Plans for a subsequent clinical trial focusing on cognition are anticipated to begin later this year.
