A promising new drug for Alzheimer's disease
A new drug for Alzheimer's disease - senile dementia - may slow the inevitable deterioration of patients by about four to seven months for a therapy duration of 1.5 years. The results of the donanemab study, which involved 1,700 volunteers between the ages of 60 and 85, were published by the Journal of the American Medical Association and presented this past Monday at the Alzheimer's Disease Association International Conference in Amsterdam.It has long been known that Alzheimer's disease is associated with the accumulation of amyloid protein in the brain, but the reasons why this happens and what the rate of brain degradation depends on are still unknown. Scientists have long tried unsuccessfully to slow the development of Alzheimer's disease with drugs targeting amyloid. In 2021, the FDA conditionally approved the drug Aduhelm, but later withdrew the decision due to a lack of evidence that it actually worked. In early 2023, the FDA approved the monoclonal antibody-based drug lecanemab (trade name Lekembi) from Japanese pharma company Eisai. And now donanemab may become the second drug that actually fights amyloid buildup.
"There is finally some hope that we can debate about. Alzheimer's is incurable. But diabetes is also untreatable, but that doesn't mean we can't meaningfully relieve patients with drugs," is how Dr. John Sims, a spokesman for developer Eli Lilly, commented on the data presented about the new drug.
But there is indeed much to debate. Both new drugs - both donanemab and Lecembi - are administered intravenously, and their use is associated with the threat of serious complications - brain swelling or bleeding. In studies of donanemab was recorded three such cases, which ended in death, specifies AP.
In addition, periodic monitoring of the brain during therapy (it is necessary to do to reduce the risk of complications) is carried out with the help of CT or MRI studies, and this is an additional cost, and a lot.
So while scientists say these drugs could usher in a new era in the fight against Alzheimer's disease, huge questions remain about when to recommend them and to which patients.
"The modest benefits would probably not be in question if the new monoclonal antibody-based drugs were low-risk, inexpensive, and easy to administer. However, this is not the case," Dr. Eric Videra of the University of California, San Francisco, commented on the new drug data in a JAMA editorial.
Indeed, monoclonal antibody therapy is very expensive: when Lekembi was approved, it became known that a year's course of treatment would cost about 65 thousand dollars.
As for the effectiveness of donanemab, researchers analyzed not only the effect of the drug on the formation of amyloid protein accumulations, but also another culprit of degenerative changes in the brain - abnormal tau protein. More tau signaled a more advanced stage of the disease.
During the 18-month study, patients who received donanemab deteriorated about 22% slower. Some of the volunteers did better - patients with low and intermediate tau protein levels progressed 35% slower. This means that the drug appears to be more effective in the early stages of the disease. But overall, donanemab slowed patients' deterioration by about four to seven months, the JAMA report said.
Meanwhile, Eli Lilly officials said the company is conducting clinical trials of another drug targeting tau protein, which developers hope will be effective in the later stages of the disease. Results are expected next year.