According to an announcement from the US Food and Drug Administration (FDA), the agency has recently approved a new therapy for Alzheimer’s disease. While this is a significant moment for a disease that hasn’t seen a new treatment in almost twenty years, the approval and data surrounding the drug remains controversial. In fact, two members of the FDA advisory committee resigned over the decision; the committee had called for more data before continuing with approval.
About Alzheimer’s Disease
Alzheimer’s disease, often just called Alzheimer’s, is a neurodegenerative illness affecting the brain that is primarily characterized by memory loss and dementia, which progressively worsens over time. Alzheimer’s disease is the leading cause of dementia around the world, being linked to around 70 percent of cases. The cause of this disease isn’t clear, but a family history of the disease, particularly in the patient’s parents, appears to be the dominant risk factor. Other possible factors may include high blood pressure, depression, and head injuries. Memory decline is often the first recognized symptom; others include mood swings, disorientation, and difficulty speaking; these symptoms worsen over time to the extent that the person cannot function in daily life; paranoia, aggression, and then apathy are common. Treatment is symptomatic and supportive, and no known medications can halt disease progression. Life expectancy following diagnosis is between three to nine years. To learn more about Alzheimer’s disease, click here.
The drug, called aducanumab (marketed as Aduhelm) was approved under Accelerated Approval protocols. This pathway allows for a drug that is intended to address a life-threatening or serious illness to be approved more quickly if it appears to be more effective than other available therapies. In addition, approval with this pathway can occur using data based on a surrogate endpoint; such an endpoint does not demonstrate clinical benefit but instead may ‘predict’ clinical benefit.
In three studies that included more than 3,000 patients, treatment with the drug was able to bring down concentrations of amyloid plaque in the brains of patients, a substance prior research has suggested plays a role in the progression of the disease. However, results were mixed as to whether this effect resulted in a slowdown in progression of Alzheimer’s disease.
Another source of concern is that patients being treated developed an array of side effects, such as headaches, bleeding, dizziness, and brain swelling. In any case, the developer of the drug, Biogen, is required to continue to study the new drug in continued trials to confirm its benefit as the first patients begin treatment with it as a marketed therapy. The drug will also be expensive, running a $56,000 annual price tag. Patients will be required to receive MRI scans after their 7th and 12th round of treatment to monitor for adverse effects.
The approval of a new drug for Alzheimer’s disease that has the potential to slow down disease progression is a big moment that should be a cause of celebration for this patient community. However, only continued study will determine if the FDA’s decision to grant Accelerated Approval was correct.