The Neuroimaging Research Group of the Barcelonaβeta Brain Research Center (BBRC), our research center, in collaboration with the AMYPAD consortium (Amyloid Imaging to Prevent Alzheimer's Disease), has demonstrated the Reliability of the centiloid scale for measuring amyloid plaques, one of the main characteristics of Alzheimer's diseaseThe work, published in the scientific journal Alzheimer's and Dementia and performed at multiple clinical centers, improves diagnostic accuracy, particularly in the evaluation of equivocal cases. The study has laid the groundwork for the European Medicines Agency (EMA) to consider this metric as a valid and robust biomarker of the accumulation of amyloid protein plaques in the brain.
The BBRC team has played a key role in this evaluation. Dr. Mahnaz Shekari, first author of the publication and researcher in the center's Neuroimaging Research Group, explains that “We have demonstrated the accuracy of the centiloid metric in patients from memory clinics, establishing it as a reliable biomarker for the diagnosis and monitoring of Alzheimer's disease. In addition, we provide a comprehensive and easy-to-follow guide to using this metric in the quantification of amyloid PETs, making it accessible to both clinical and medical teams. “clinicians and researchers alike.”
EMA support: an achievement for the team
The EMA’s Committee for Medicinal Products for Human Use (CHMP) has recognised the centiloid unit as a sensitive and robust universal measure of overall amyloid burden in the brain when used in clinical trials, provided appropriate quality control procedures are followed. This allows for consistent comparisons of amyloid PET scans between different tracers and procedures, supporting Alzheimer’s disease clinical trials.
“The resolution issued by the EMA Committee for Medicinal Products for Human Use is an incredible achievement for the team,” ensures the Dr. David Vállez, director of the center's Neuroimaging Platform and former data manager and researcher at AMYPAD. “This support validates the reliability and applicability of the centiloid method in the clinical setting, which is key considering the evolution of clinical trials and the expected arrival of disease-modifying therapies.”, he explains.
A universal measure for clinical practice
The results of this study could not only benefit clinical teams, but would also be very advantageous for people with Alzheimer's disease. undergoing anti-amyloid drug treatment. “Quantitative centiloid metrics improve diagnostic accuracy, particularly when evaluating equivocal cases with intermediate levels of amyloid”, explains the Dr. Juan Domingo Gispert, scientific collaborator of the BBRC. In these cases, visual assessments can be challenging and vary significantly depending on the reader's experience. According to the researcher, “The centiloid scale adds prognostic value, improves the differential diagnosis of dementias and is the best predictor of the clinical benefit of anti-amyloid therapies.”
With the anticipated rise of anti-amyloid drugs and their wider clinical use, the centiloid metric will be crucial to assess drug efficacy and manage dosing effectively. According to the EMA Qualified Opinion, “The use of the centiloid scale may provide a potential reference measure for future monitoring therapies or follow-up scanning”. The full document can be consulted here.
Bibliographic reference
Shekari, Mahnaz, et al. "Stress testing the Centiloid: Precision and variability of PET quantification of amyloid pathology." Alzheimer's & Dementia 20.8 (2024): 5102-5113.
