RG6102 is a bispecific 2+1 monoclonal antibody (mAb) under development for the treatment of Alz- heimer’s disease (AD). It combines the anti-amyloid beta antibody gantenerumab with a transferrin receptor 1-binding “Brain Shuttle” module, enabling active receptor-mediated transport across the blood–brain barrier.

In preclinical studies, RG6102 has shown superior distribution, target engagement and amyloid plaque clearance compared with gantenerumab. In a human Phase Ia study, there was a markedly increased cerebrospinal fluid (CSF)/plasma ratio for RG6102 compared with typical mAbs.

Brainshuttle AD is a 28-week, randomised, global, multicentre, double-blind, placebo-controlled, parallel- group Phase Ib/IIa study evaluating the safety, tolerability, immunogenicity and pharmacokinetics/phar- macodynamics (PK/PD) of RG6102. Multiple-ascending intravenous doses of RG6102 are administered every 4 weeks to patients with prodromal or mild-to-moderate AD. The study consists of a screening period, a double-blind treatment period and a safety follow-up period.

The primary objective is to evaluate the safety and tolerability of RG6102. Secondary outcome measures include the change from baseline in brain amyloid load, plasma and CSF concentration of RG6102 and incidence of anti-drug antibodies to RG6102. Exploratory endpoints include the clinical effect of multiple doses of RG6102 on clinical outcome measures and on various PD biomarkers.

Recruitment for Brainshuttle AD is currently ongoing.