After the pre-clinical development stage, without appropriate measures of target engagement, determining the effect of the current monoclonal antibodies cannot be assessed in the absence of a robust clinically meaningful effect over a short period of time, a thus far elusive goal in neurodegenerative diseases. If target engagement and clear effects on diverse tau populations can be demonstrated, clinical trials will be informative whether or not they produce positive results, because they will provide important insights to human tau pathophysiology that can guide future work.
