Maseru __ World Health Organisation (WHO) published the preferred product characteristics (PPC) of blood-based biomarker diagnostics for Alzheimer disease (AD).

According to the health organization, the PPC aims to inform the development of blood-based biomarker diagnostics or tests for the disease by ensuring that tests achieve optimal clinical performance and will be suitable for future use in a range of settings including low- and middle-income countries, including Lesotho.

It further states that the primary audience for this PPC includes entities intending to eventually seek WHO policy recommendations and prequalification, adding that it offers guidance to funders, researchers, product developers and regulatory agencies in the development and implementation of diagnostic tools using blood-based biomarkers for AD.

WHO notes that dementia is a major cause of disability and the seventh leading cause of death globally, and in 2019, over 55 million people were estimated to be living with dementia, of which 60–70% were caused by AD.

It is also recommended that receiving a timely and accurate AD diagnosis is a prerequisite for accessing services and support for the person, families and care partners.

The organisation also indicates that currently, a diagnosis of AD is based on clinical judgment, which can be supported by imaging techniques and laboratory analysis of cerebrospinal fluid (CSF).

However, it is noted that there is a global shortage of qualified health professionals and access to imaging and CSF analysis is similarly limited, particularly LMICs, where the number of specialized healthcare workforce is low.

The use of blood-based biomarkers therefore has enormous potential to support health systems in improving the diagnosis of AD and this is especially relevant in settings where the size of the specialized healthcare workforce is significantly low and health system infrastructure and funding are unable to provide specialized neurological services sustainably to populations.

The PPC specifies the intended use and target population for these tests and outlines its desired clinical performance.

It also emphasizes the importance of providing guidance on how to interpret results, which must consider factors such as age, sex, genetic mutations, medications, comorbidities, local or regional conditions and disease stage.

Additionally, the PPC highlights key aspects that need to be considered, including accessibility, affordability, workforce capacity and training, requirements of technical support and equipment maintenance.

The PPC was developed in line with WHO target product profiles, preferred product characteristics and target regimen profiles: standard procedure, second edition, 2024.