Roche announced significant progress in its Alzheimer’s disease research portfolio during the Alzheimer’s Association International Conference (AAIC) 2025 in Toronto.
The company presented detailed results from its investigational therapy trontinemab and showcased its Elecsys pTau217 blood test, both of which aim to transform the detection and treatment of Alzheimer’s disease.
Advancing trontinemab with Brainshuttle technology
Roche’s investigational therapy trontinemab is a bispecific monoclonal antibody developed using the company’s proprietary Brainshuttle technology. This design helps transport therapeutic antibodies across the blood-brain barrier more effectively, allowing for targeted clearance of amyloid-beta plaques in the brain. In the ongoing Phase Ib/IIa Brainshuttle AD study, trontinemab produced rapid and robust reductions in amyloid plaque levels.
In the higher 3.6 mg/kg dose group, 91 percent of participants dropped below the amyloid PET positivity threshold within 28 weeks of treatment, and 72 percent achieved deep clearance to below 11 centiloids.
The treatment also generated early and meaningful improvements in cerebrospinal fluid and plasma biomarkers linked to Alzheimer’s disease, including total tau, phosphorylated tau 181, phosphorylated tau 217, and neurogranin.
Safety profile and readiness for Phase III
Safety results remained favorable, with amyloid-related imaging abnormalities with edema or effusion occurring in less than five percent of patients. All cases were radiographically mild, and symptoms, when present, were short-lived. Roche confirmed that trontinemab continues to show a tolerable safety profile, supporting the decision to advance the drug to late-stage testing.
Plans for multiple Phase III studies
The company plans to begin two pivotal Phase III trials, named TRONTIER 1 and TRONTIER 2, in the second half of 2025 to evaluate trontinemab in early symptomatic Alzheimer’s disease. A third Phase III study will test the therapy in individuals with preclinical Alzheimer’s who are at high risk of cognitive decline. Roche aims to determine whether early intervention with trontinemab can delay or even prevent progression to symptomatic disease.
Expanding diagnostics with the Elecsys pTau217 blood test
Alongside its pharmaceutical advances, Roche highlighted progress in diagnostics through the Elecsys pTau217 assay. This high-throughput, fully automated blood test detects amyloid pathology with accuracy comparable to positron emission tomography scans and cerebrospinal fluid testing. The company designed the test to serve as a scalable, accessible tool for both rule-in and rule-out diagnosis of Alzheimer’s disease in a range of healthcare settings.
Integrating diagnostics into clinical trials
Roche intends to integrate the Elecsys pTau217 test into its upcoming trontinemab clinical trials. By using this assay to identify eligible participants, Roche can accelerate recruitment and ensure a more diverse study population.
The test’s simplicity, requiring only a standard blood draw analyzed in a clinical laboratory, could allow healthcare providers to diagnose Alzheimer’s earlier and more efficiently.
This approach has the potential to shorten the diagnostic process, which currently takes an average of 2.8 years from the onset of symptoms for those who are eventually diagnosed. Roche estimates that as many as 75 percent of people with symptomatic Alzheimer’s disease worldwide remain undiagnosed.
Leadership commentary on strategy and impact
Levi Garraway, Roche’s Chief Medical Officer and Head of Global Product Development, emphasized the significance of combining disease-modifying therapies with advanced diagnostics.
He stated that pairing new treatment approaches like trontinemab with innovative tools such as the Elecsys pTau217 test could enable earlier and more effective intervention for Alzheimer’s disease.
Matt Sause, CEO of Roche Diagnostics, noted that the blood test matches PET scan accuracy but can be performed far more simply, giving caregivers, patients, and families timely and clear answers.
A comprehensive approach to changing Alzheimer’s outcomes
Roche’s dual approach to Alzheimer’s disease, focusing on both treatment and diagnosis, reflects a comprehensive strategy aimed at changing the trajectory of the condition. The upcoming Phase III trials and continued validation of the Elecsys pTau217 test represent critical steps toward Roche’s goal of delivering earlier intervention, improved patient outcomes, and a shift in how the disease is managed globally.
How Roche’s Alzheimer’s could impact CNS Drug Development
Advancing biologic delivery in CNS disorders
Roche’s recent progress in Alzheimer’s disease could mark a turning point for central nervous system (CNS) drug development. At the Alzheimer’s Association International Conference (AAIC) 2025, the company presented promising data on trontinemab, a bispecific monoclonal antibody using its proprietary Brainshuttle technology. This delivery system allows antibodies to cross the blood–brain barrier more efficiently, addressing one of the largest obstacles in CNS therapeutics. Its success could inspire more pharmaceutical companies to invest in targeted delivery technologies for neurodegenerative diseases.
Setting new clinical performance benchmarks
Trontinemab’s early-phase results showed rapid and robust amyloid plaque clearance, with significant improvements in biomarkers such as total tau, phosphorylated tau 181, phosphorylated tau 217, and neurogranin. In the highest dose group, 91 percent of participants fell below the amyloid PET positivity threshold within 28 weeks.
These results raise the performance bar for biologics in CNS drug development and demonstrate the value of biomarker-based progress tracking.
Integrating diagnostics into therapeutic strategies
The Elecsys pTau217 test offers PET-comparable accuracy using only a blood draw. This diagnostic tool can identify amyloid pathology earlier, streamline trial recruitment, and align treatment with the right disease stage.
Roche’s strategy of integrating a companion diagnostic alongside a novel therapy provides a model for future CNS drug launches, where diagnostics become essential to both clinical and commercial success.
Influencing industry priorities and investment
Roche’s Alzheimer’s program illustrates the potential of combining advanced drug delivery with scalable diagnostics. It highlights a pathway for CNS pipelines to focus on early detection, targeted delivery, and biomarker-driven treatment strategies.
If trontinemab and pTau217 achieve commercial success, they could shift industry investment toward integrated solutions for neurodegenerative diseases, accelerate regulatory acceptance of biomarker-based endpoints, and influence how CNS drug candidates are developed and brought to market.
