MAPT and Alzheimer disease: This should make RI‐AG03 efficacious for the treatment of all Tauopathies whether the aggregating species has only 306VQIVYK311 containing Tau aggregates (3R Tauopathies) or both 306VQIVYK311 and 275VQIINK280 containing Tau aggregates (e.g., AD and 4R Tauopathies).