Annovis is attempting to lessen a-synuclein-induced pathogenesis by reducing the synthesis of the a-synuclein protein.

PNT article: First Patients Dosed in Clinical Trial Investigating ANVS401 as Treatment for Parkinson's and Alzheimer's
First Patients Dosed in ANVS41 Trial for Treating Parkinson's, Alzheimer's

Trial Record: Posiphen Dose-Finding, Biomarker Study in Early Alzheimer's and Parkinson's Patients
https://clinicaltrials.gov/ct2/show/NCT04524351

SoPD blog post (background info): Disney's "Attack of the synucleozid from Jupiter"
Disney’s “Attack of the synucleozid from Jupiter” – The Science of Parkinson's

Posiphen (ANVS401) mode of action:
Posiphen is an orally available small molecule drug that inhibits the translation of a-synuclein, by increasing the affinity of Iron Regulatory Protein-1 (IRP1) to the Iron-Response Element (IRE) of the SNCA gene's messenger RNA (mRNA). This represses translation by preventing the association of the mRNA with the ribosome.