Radiotracer targets β‑Amyloid for early Alzheimer’s detection

Despite the absence of a cure, the urgency around Alzheimer’s disease has shifted toward detecting the disease as early as possible to limit neurological damage and enable timely intervention. Current diagnostic strategies rely on Positron Emission Tomography (PET) imaging with radiotracers such as βamyloid binders ¹⁸F-flutemetamol and ¹⁸F-florbetapir. While approved for clinical use in the US and UK, these tracers bind only to βamyloid in its plaque form, meaning they primarily identify the disease at later stages, which misses the critical window for early intervention.

This limitation has intensified efforts to uncover biomarkers capable of revealing the disease at its earliest stages. At the University of Cambridge, Research Associate Dr. Yanyan Zhao is tackling this challenge by developing a novel radiotracer designed to target βamyloid oligomers, highly toxic aggregates believed to trigger neuronal damage before plaques form.

At ELRIG Drug Discovery 2025, Europe’s leading conference for early-stage drug discovery, researchers and industry experts gathered to showcase innovations shaping the future of therapeutics. Catching up with Dr. Zhao on the conference floor, we explored her pioneering approach to Alzheimer’s research. She outlined the beginnings of her work and the promise it holds not only for enabling earlier, more precise detection of the disease, but also for offering valuable insights into drug discovery and development.

How do you intend to make early-diagnosis possible?

Dr. Zhao: The new technique we are working on, is trying to detect early-stage Alzheimer’s through β-amyloid in its oligomeric form, which is considered highly cytotoxic. These oligomers attack the neuron communication pathways and so if we can effectively detect the presence of oligomers in the brain, we can diagnose early and begin treatment as soon as possible.

What approach have you taken to detect the presence of Aβ oligomers and have you faced any challenges?

Dr. Zhao: Compared to other clinical diagnostic tests, such as behavioral assessments or Positron Emission Tomography (PET) scans that detect β‑amyloid in its fibril form, these methods typically identify Alzheimer’s only at a late stage. Our work focuses on finding earlier biomarkers. We are working on producing a radiotracer that can be injected into the patient, by-pass into the brain, to produce a clear PET image of where the toxic oligomers reside in the brain for early detection.

At present, we have conducted extensive in vitro testing, though one of the main challenges has been getting the radiotracer to cross the blood–brain barrier. This research has been inherently challenging because the oligomer is in a transitional state, it shortens the window of detection before fibril formation. Despite this limitation, it does offer significant promise to be a sensitive biomarker and shows potential as an early diagnostic.

What are the next steps you envision for this research?

Dr. Zhao: I very much hope to build a large-scale screening that uses AI to conduct ligand-based virtual screening. The goal is to build a database that can be used to determine biological targets and screen novel therapeutics to give indication of binding and probability, offering insights for Alzheimer’s drug discovery.

Missed the ELRIG Drug Discovery 2025 conference this year? Explore some of our wider coverage of the event here.