Aducanumab is a recently-approved promising drug that treats Alzheimer's disease. No other drugs have been approved for this disease since 2003. Why was there so much controversy surrounding the release of this new drug?
It was provisionally approved by the Food and Drug Administration (FDA), the United States government agency responsible for regulating food and drugs. Based on current data, certain experts have questioned its effectiveness and whether the drug actually slows the course of the disease. Because of this, new clinical studies have been requested to demonstrate its efficacy and maintain FDA approval. It has not yet been approved in Europe.
Was it a hasty approval?
It was approved through an expedited procedure, which is used on certain occasions, so it did not follow the usual process. There are discrepancies between studies, so the new research will determine whether the drug really does modify the course of the disease. The subject will be hotly debated over the coming months or years.
The only treatment we can currently offer Alzheimer’s patients are drugs to improve symptoms. There are also non-pharmacological treatments that complement the comprehensive treatment of the disease.
What is the current evolution of Alzheimer's disease? Has patients’ prognosis improved in recent years?
The disease can only be treated for symptoms, that is, their objective is to improve the patients’ symptoms, such as cognition problems or behaviour disorders. They are drugs that do not modify the course of the disease and were approved more than 20 years ago.
There has been much research into drugs that modify the natural course of the disease, such as drugs that remove beta amyloid, a protein that is deposited within the brain in Alzheimer's disease. Or drugs against the tau protein, another key protein in the disease. However, for the moment, we can only offer these drugs to patients who participate in clinical trials, and not on a regular basis.
Do we know why beta-amyloid and tau proteins are deposited in the brain? What hypothesis is there in this regard?
What we know today is that it is a very common disease that affects two out of 10 people aged over 80, and that the malfunction and accumulation of these proteins probably occurs between 10 and 20 years before the onset of patients’ symptoms. But the exact cause why this occurs is still unknown.
What lines of research are currently most promising?
There are two main lines of research. The first includes the improvement of diagnosis, prognosis and treatment. The second is focused on finding the causes of the pathology and its consequences. Regarding the diagnosis of the disease, a lot has changed in recent years. We now have a variety of biomarkers that help us diagnose the disease and that we use in the Hospital during routine clinical practice.
And, there is research on the progression of the disease, which can take a very diverse evolution. One of the big problems today is that we don't know how each person will evolve. There are patients whose dementia may evolve to moderate/advanced levels in 2-3 years, and others who do not reach this level until 10-15 years after diagnosis. We cannot currently predict the course of the pathology for each patient, but there is a lot of ongoing research in this regard. Obviously, the line of research into therapies that modify the course of the disease is one of the most relevant.
We were one of the first hospitals in Spain to use cerebrospinal fluid biomarkers. This has helped many families, and as a professional I am proud to be part of that.
What are the best and the worst parts of your job?
Treating diseases that are incurable and progressive, such as Alzheimer's, is difficult. But despite everything, the human aspect is one of the best parts of my job. Especially the interaction with the patient and with their family. The empathy and contact that is established with them is one of the things that satisfies me the most about being a doctor.
Furthermore, it is a disease that still has a long way to go. Those of us who dedicate ourselves to this speciality are very excited about improving the treatments we can offer. And even more so when you work in a centre like the Hospital Clínic where research is carried out parallel to clinical practice. We were one of the first hospitals in Spain to use cerebrospinal fluid biomarkers. And this is just one of our research results we have been able to apply to our clinical practice. It has helped many families and as a professional I am proud to be part of that.
Do you think there will be a cure for Alzheimer's disease in our lifetime? And its chronification?
We must be optimistic and think that things will change. There has been quite significant progress, for example in diagnosis. The investigations that have not turned out as we expected at the level of treatments, have served to guide us in our search. Current strategies will probably have to take another direction, and we will need to rely on earlier diagnoses. The knowledge acquired in “failures” should help us to improve the future.
I would like to acknowledge the work caregivers carry out. It is a job that is often overlooked, but it is tough and essential for patients’ well-being.
What is the biggest challenge you have encountered as a specialist in neurology?
I have worked for many years in the diagnosis and treatment of young patients with Alzheimer's disease, that is, patients aged under 65. In these cases, the social and family impact is even greater than in older patients. One of the most important challenges we have is trying to be a reference centre for these patients. There are few places that have the diagnostic tools we can offer, or the experience in treating these types of patients. We should be able to organise ourselves to ensure that all patients who show symptoms, especially younger age groups, have access to the diagnostic tools that the public health system has approved.
The biggest challenge is diagnosing these diseases in very early stages, this implies training both health workers and the population, and having agile referral systems, so that the patient who shows signs of cognitive impairment can access specific units without significant delays, ensuring the best possible diagnosis.
What would you say to a person who is diagnosed with Alzheimer's today?
Alzheimer's disease is not yet curable, but it is not simply a very advanced dementia, which is what many people think. Alzheimer's disease usually has a very long course and we try to diagnose it at early stages. Therefore, despite having some cognitive issues, the patient can lead a relatively normal life during some years. Make decisions, organise their future, enjoy life, etc.
I would also like to acknowledge the work caregivers carry out. It is a job that is often overlooked, but it is tough, and essential for patients’ well-being. Alzheimer's disease is one of the most expensive diseases to care for, and much of that cost is borne by the family.