Experts in Alzheimer’s research, on the other hand, view antibody drugs rather critically: despite proven reduction of Aß deposits, the benefit for the patient remains questionable, since no antibody has yet succeeded in halting or alleviating the disease. In all cases, the deterioration of cognitive decline is minimally slowed, but not slowed. Moreover, the proven “efficacy” in terms of reducing senile plaques is dearly bought with serious, sometimes fatal, side effects.
These side effects are referred to as ARIA(Amyloid-Related Imaging Abnormalities) in the medical community. They manifest as undesirable changes in MRI scans and occur with all anti-amyloid antibodies. In patients treated with these agents, study physicians observed ARIA in the form of brain swelling and cerebral hemorrhage or iron deposition, which in some cases was fatal. But even if the ARIA are clinically more harmless, this means an enormous additional diagnostic effort for the treating physicians, which is associated with high additional costs – and not least with immense stress for the patients.
ARIA do not appear to be the only side effect of these agents, as an Australian research group has discovered in a recent study: To do so, the scientists took a closer look at the side effects of anti-Aß drugs, i.e., their triggering potential for ARIA, and their effects on brain volume. The results of this scientific study were published in the highly respected medical journal Neurology in early 2023.
Paradoxically, the Australian research team found in this study that all representatives of this group of drugs also promoted a shrinking of the brain volume (brain atrophy), the structural cardinal symptom of Alzheimer’s disease. Since brain atrophy was accelerated, especially in the patients with the side effects, this would be more than concerning since a fairly high proportion of patients had these adverse side effects: with the newest agent, donanemab , about a quarter of participants suffered from brain edema and about a third from brain hemorrhage. These patients in particular are thus affected by brain atrophy. The authors therefore derive the following specific recommendations from their findings: