Could Viagra help prevent and treat Alzheimer’s disease?
US researchers says sildenafil—the generic name for Viagra—may be a useful treatment to help prevent and treat Alzheimer’s disease.
A new study led by the Cleveland Clinic’s Genomic Medicine Institute found that sildenafil, an oral medicine used to treat erectile dysfunction and pulmonary arterial hypertension, is associated with 69% reduced likelihood of developing Alzheimer’s disease.
According to the Cleveland Clinic, researchers used a large gene-mapping network and integrated genetic and other data to determine which of the over 1,600 US Food and Drug Administration-approved drugs could be an effective treatment for Alzheimer’s disease.
Researchers also pinpointed drugs that target both amyloid and tau as having higher scores compared to drugs that target just one or the other.
“Sildenafil, which has been shown to significantly improve cognition and memory in preclinical models, presented as the best drug candidate,” said Dr. Feixiong Cheng, the research team lead.
The study, published in Nature Aging, also found that people who are on sildenafil were 69% less likely to develop Alzheimer’s disease than those who are not taking the medication based on medical database of more than seven million individuals in the United States.
“Notably, we found that sildenafil use reduced the likelihood of Alzheimer’s in individuals with coronary artery disease, hypertension and type 2 diabetes, all of which are comorbidities significantly associated with risk of the disease, as well as in those without,” added Cheng.
Though the findings look promising, Cheng said it needs more exploring, ”Because our findings only establish an association between sildenafil use and reduced incidence of Alzheimer's disease, we are now planning a mechanistic trial and a phase II randomized clinical trial to test causality and confirm sildenafil's clinical benefits for Alzheimer's patients.”
University of Edinburgh Prof. Tara Spires-Jones, deputy director of the Centre for Discovery Brain Sciences, said more work will be needed to know if sildenafil can indeed lower the risk for Alzheimer’s disease.
“While these data are interesting scientifically, based on this study, I would not rush out to start taking sildenafil as a prevention for Alzheimer’s disease,” Spires-Jones said in a statement published by the Science Media Centre.
Alzheimer’s disease is the most common cause of dementia among older adults. According to the World Health Organization, over 55 million people live with dementia worldwide and there are nearly 10 million cases every year. Despite this, there is currently no effective treatment available for dementia, though there are numerous treatments that are in various stages of clinical trials.
Meanwhile, sildenafil was originally developed by Pfizer for treatment of hypertension and angina pectoris (chest pain due to heart disease) as it relaxes or widens blood vessels that allows greater blood flow.
While it was under clinical trials, researchers reportedly found that sildenafil was more effective at inducing erections than treating angina. It was in 1998 when the US FDA approved Viagra as the first oral treatment for erectile dysfunction.