054 Baseline characteristics of the Phase III GRADUATE studies: investigating subcu- taneous gantenerumab in early AD

Gantenerumab is a fully human anti-amyloid beta (Aβ) monoclonal immunoglobulin G1 antibody in devel- opment for the treatment of Alzheimer’s disease (AD). Two ongoing multicentre, randomised, double-blind, placebo-controlled, Phase III studies, GRADUATE I ( NCT03444870 ) and GRADUATE II ( NCT03443973 ), are assessing the efficacy and safety of subcutaneous gantenerumab in early AD for 27 months. Eligible participants had prodromal AD or probable AD dementia; demonstrated abnormal memory using the Free and Cued Selective Recall Test; met criteria for the Mini-Mental State Examination (≥22) and Clinical Dementia Rating – Global Score (0.5-1); and had confirmed Aβ pathology. Participants were randomised 1:1 to receive subcutaneous gantenerumab or placebo, administered at study site or via home nursing. The study drug is titrated in three up-titration steps (120 mg, 225 mg, 510 mg monthly) over 9-months to the target 1,020 mg monthly dosage. All participants receive the same titration and target dose, regardless of apolipoprotein E β4 status. The GRADUATE primary endpoint is change from baseline to Week 116 in Clinical Dementia Rating scale – Sum of Boxes. Secondary efficacy measures, fluid and imaging biomarkers, and safety are also being assessed. Recruitment is complete. Participants were enrolled from 32 countries across 5 continents. Detailed baseline characteristics will be presented.