Alzheimer's Disease can seem like a tragic inevitability for those who have rare genetic forms of the disease. The neurodegenerative condition currently has no cure, and scientists aren't even entirely set on what causes it, but an anti-amyloid drug, gantenerumab, could change all that.

Published in the Lancet Neurology journal, a new study found increased doses and long-term use of the drug could delay the onset of Alzheimer's symptoms for those with a genetic form of the disease. The fact that this drug could work will also point experts towards a potential cause for Alzheimer's Disease: amyloid build-up. This has been a theory among experts for years that the build-up of amyloids in the brain causes cognitive decline.

Because the anti-amyloid drug seemingly worked in this limited study, it could indicate this theory is correct, which would immediately open potential treatments and protection against dementia by removing the plaque.

"It suggests that extended use of anti-amyloid treatments may delay or prevent the onset of dementia symptoms. But these results highlight the importance of early intervention and longer-term follow-up in determining the benefits and risks of dementia treatments," said Dr Susan Kohlhaas, Executive Director of Research and Partnerships at Alzheimer's Research UK.

It's important to highlight that the study was prematurely ended by its sponsor, resulting in only a small number of the original 74 participants completing three years of treatment. The researchers and charity experts have called for more research into this drug and how it interacts with other common forms of Alzheimer's and dementia.

Prof Randall J. Bateman, the senior author of the study, pointed out: "Everyone in this study was destined to develop Alzheimer's disease and some of them haven't yet."

This implies that the results are solely applicable to those with genetic or familial Alzheimer's disease, which accounts for less than 1% of Alzheimer's cases, according to the Alzheimer's Association.

There is hope that the participants who continue with the treatment will never show symptoms, but as the author confessed: "We don't yet know how long they will remain symptom-free – maybe a few years or maybe decades."

Nevertheless, the professor remains "highly optimistic", as reported by Alzheimer's Research UK. He believes this study could provide the first clinical evidence of preventative measures that could offer hope to those genetically predisposed to Alzheimer's Disease.