Fig. 2From: Evaluation of the efficacy, safety and tolerability of orally administered BI 409306, a novel phosphodiesterase type 9 inhibitor, in two randomised controlled phase II studies in patients with prodromal and mild Alzheimer’s diseaseStudy design for prodromal and mild Alzheimer’s disease studies. All n numbers represent the planned values. BID, twice daily, QD, once daily; R, randomisationBack to article page