With a considerable increase in Alzheimer’s cases worldwide over the years, the medical community desperately needs effective treatment now more than ever before.
In September this year, pharmaceutical companies Biogen and Eisai published encouraging results from the clinical trials of a new drug called Lecanemab for Alzheimer’s patients. Lecanemab is a monoclonal antibody treatment that has been shown to reduce cognitive decline by almost 27% among patients with early-stage Alzheimer’s compared to patients on placebo treatment after one and a half years.
Industry observers say the positive results from the trial could offer some hope to millions of Alzheimer-afflicted people worldwide, but the whole is bereft of any treatments.
Amid the rise in excitement for the new drug, many questions still linger. The chief among them is why this new treatment delivered such positive outcomes when other therapies based on similar strategies have failed. The signature feature of the illness: an amyloid plaque build-up in the brain – protein clumps that disrupt the normal functioning of neurons and other cells, has always been a subject of wonder for researchers who’ve tried to target it and subdue it with several clinical trials over the years.
But the drugs that inhibit or break down these plaques haven’t successfully subdued the symptoms. Laenamab is the first treatment to do so. Drug maker Eisai has already applied for “accelerated approval” of its drug Lecamoab with the US Food and Drug Administration. If things go as planned, the drug could be licensed for medical use by January 2023. However, essential concerns still need to be addressed even if the final published data shows promising results.
Overcoming concerns
There is, however, a slight chance of substantial side effects with the Lacenemab drug, including brain bleeding and swelling. Most patients are unaware of when it occurs, but almost 3% of those who took the trials suffer from small bleeds in the brain.
The severity of the bleeding is still not known. Maybe doctors could predict when it occurs and who is most likely to experience it. But it will take some years after allowing the drug for clinical practice to understand better its side effects and the ways to manage them effectively.
Patients prescribed the new drug may need to undergo regular MRI scans to check for brain bleeding and swelling. But these are an enormous addition to the already costly healthcare costs of treating Alzheimer’s. And we still have no idea how much this new drug will cost.
Another concern is identifying patients with early-stage Alzheimer’s. It means doctors must refer patients to memory clinics as early as possible. But, many of these referred patients with mild memory loss symptoms may not have Alzheimer’s. After all, memory lapse is a part of ageing and doesn’t always result in Alzheimer’s.
Final takeaway
The phase 3 trials show that Lecanemab did slow down the cognitive decline rate in patients with early-stage Alzheimer’s disease and mild cognitive impairment by about 27% over 18 months. The effect is similar to the current drugs, but these don’t impact the underlying causes of Alzheimer’s the way the new drug does.
Suppose the positive effects of the new drug remain stable for more than 18 months. In that case, any patient with mild cognitive impairment symptoms could gain an extra 19 months of independent life, more than the six years of stipulated independent life. Regulators, patients, and doctors need to view the side effects and risk factors before arriving at a conclusion.