On 29 November, the detailed results of the phase 3 clinical trial of lecanemab were presented at the Clinical Trials in Alzheimer's Disease (CTAD) conference. They confirm what was announced at the end of September 2022 in a press release: although it does not stop the disease, the drug slows its progression. The Food and Drug Administration (FDA) has accepted the drug for marketing, following an accelerated application.
The scientific community and all those affected by Alzheimer's disease were eagerly awaiting the detailed results of the phase 3 clinical trial on lecanemab, presented in San Francisco at the CTAD on 29 November 2022. The aim of this drug, which belongs to the family of monoclonal antibodies, is to effectively target aggregates of the beta-amyloid protein, which are presumed to be responsible for the degeneration of nerve cells in the brain in Alzheimer's disease. During the conference, Eisai and Biogen, the two companies leading the clinical trial, provided more details on the patient groups treated and the side effects.
The study involved 1795 participants, aged 50 to 90 years, with early-stage memory problems. For 18 months, half of the panel received the antibody intravenously, the other half a placebo. Overall, lecanemab reduced the progression of Alzheimer's disease by 27% in those affected at an early stage. Although the result of the clinical trial is clear, it only shows a slowing down of the disease and not its suspension. Prof. Giovanni Frisoni, Director of the Memory Centre at the University Hospitals of Geneva, is also cautious: "This result is equivalent to reducing the slope of the disease, but not to levelling it. However, the 27% benefit is an average and some patient groups may be more sensitive to this drug than others. It will be interesting in the future to see if the reduction in progression is higher in certain groups of people, in whom the 27% may be higher.
The presentation of the results also highlighted the side-effects found in those who received the drug. Localised cerebral oedema was observed in 13% of those treated with the drug and small haemorrhages in 17% of them, while the frequency was 2% and 9% in those treated with placebo. It should also be noted that since the end of the clinical trial, two people who received the treatment have died, but the link between the drug and death is not clearly established.
However, it is important to note that lecanemab is the first drug developed to date that definitely curbs the progression of the disease. It is a promising new avenue of care for Alzheimer's disease.
The application to market the drug in the United States has been submitted to the Food and Drug Administration (FDA). A positive response was communicated on 6 January 2023. The European Medicines Agency (EMA) is expected to issue its opinion at the end of the first quarter of 2023.
Publication of the study results in The New England Journal of Medecine