At the Alzheimer's Association International Conference (AAIC) 2026 in London, researchers presented data on trontinemab, an anti-amyloid treatment that has been engineered to more effectively cross the blood-brain barrier via the transferrin receptor. Five oral presentations formed a Featured Research Session held on 14 July, covering long-term data from the Phase Ib/IIa Brainshuttle AD study and the design of a new prevention trial, PrevenTRON.
The Brainshuttle AD study is a Phase Ib/IIa randomised, double-blind, placebo-controlled trial of approximately 210 participants with mild cognitive impairment or mild to moderate dementia due to Alzheimer's disease, confirmed as amyloid-positive by PET. Participants receive intravenous trontinemab, or placebo, every four weeks, with an open-label extension in which all participants receive trontinemab.
Interim data from the Brainshuttle AD open-label extension reported continued amyloid clearance. At the 3.6 mg/kg dose, 92% of participants fell below the amyloid positivity threshold of 24 centiloids after 28 weeks of treatment, compared with 65% at 1.8 mg/kg, and reduction from baseline was maintained across the one-year extension. Amyloid-related imaging abnormalities with oedema (ARIA-E) were observed in fewer than 5% of participants across the two dose cohorts, a rate lower than those reported for the approved anti-amyloid antibodies. Interim biomarker results showed sustained reductions in cerebrospinal fluid and plasma markers, including total tau, pTau181, pTau217 and neurogranin.
Further presentations covered modelling of amyloid clearance used to inform the dosing regimen for the ongoing Phase III TRONTIER 1 and 2 studies in early symptomatic Alzheimer's disease, and evidence presented in support of preclinical Alzheimer's disease as a stage for intervention.
Roche also presented, for the first time, the rationale and design of PrevenTRON, a Phase III trial of trontinemab in preclinical Alzheimer's disease. The study plans to enrol cognitively unimpaired individuals at high risk of progression to symptomatic disease, with the Elecsys pTau217 blood test used to help identify potential participants.
Read more: https://www.roche.com/media/releases/med-cor-2026-07-07
