Immunotherapy and Parkinson’s disease

Immunotherapy represents a therapeutic model based on an action on the immune system. Practiced for a long time in oncology, she knows her letters of nobility in neurology for a few years in the treatment of multiple sclerosis with mono-clonal antibodies. An interesting approach has emerged in Parkinson’s disease via anti-alpha-synuclein immunotherapy. Alpha-synuclein is an abundant protein in the central nervous system (glial cells, cortex, black matter). It plays an important role in brain plasticity. As a result of various factors (genetic, toxic) the protein undergoes a change in conformity allowing it to aggregate in the form of toxic agglomerates (intra and extracellular) leading to neuronal death and the expression of the various signs of Parkinson’s disease. Immunotherapy can be active (basis of the vaccine: an antigen is administered to cause antibody production) or passive (administration of antibodies produced outside the host organism). In Parkinson’s disease, various mono-clonal antibodies have been used with varying degrees of success. The use of Prasinezumab (PASADENA study) on several hundred patients has led to an improvement in certain parameters of the disease (including the motor score) to hope for an impact on the course of the disease. The effect could be more interesting at the beginning of the disease to avoid “the neurodegenerative cascade” before the use of treatments called symptomatic of the disease (L-dopa or dopaminergic agonist). This will need to be confirmed by further population studies but the effects observed in multiple sclerosis (another model of neurological disease where there is a neurodegenerative component alongside the inflammatory component) with mono-clonal antibodies seems hopeful. Treatment early (or even at the pre-symptomatic stage) could give hope for a blockage of the neurodegenerative process when we know that current symptomatic treatments are often initiated in patients who have already lost more than half of their dopaminergic neuronal potential.