Salvaging CNS Clinical Trials halted due to COVID‐19

Geerts, Hugo; van der Graaf, Piet H.

The COVID‐19 pandemic has halted many ongoing CNS clinical trials, especially in Alzheimer’s disease. These long‐duration trials involve many stakeholders, especially the patients and their family members, who have demonstrated their commitment to developing new therapeutic interventions for this devastating disease. We certainly do not want to lose all the knowledge we have gained from these ongoing trials because of the pandemic. While some of these trials will need to restart, others can re‐start at different points along the trial protocol with substantial protocol amendments. However, there is an urgent need to combine useful information from the completers with those subjects undergoing complex protocols deviations and amendments after re‐start. We propose the concept of mechanistic modeling‐based virtual twin patients as a possible solution to harmonize the readouts from these complex and fragmented clinical datasets in a biologically relevant way.