Section 1.1: The Challenge of Diagnosing Alzheimer’s

Unlike lung cancer, which has identifiable risk factors such as smoking, Alzheimer’s presents a more complex picture. While it constitutes 60-70% of dementia cases, many risk factors are not clearly defined. Diagnosis typically relies on a combination of clinical assessments and other tests. Although risk factors can be identified during a patient's life, a definitive diagnosis requires analysis after death.

Advanced imaging techniques can detect the presence of plaques, which often form long before symptoms arise. As brain cells deteriorate, their energy consumption diminishes, making these changes detectable. Other methodologies examine amyloid plaque buildup or alterations in brain microstructure.

Additionally, cerebrospinal fluid (CSF), which surrounds the brain and spinal cord, can reveal significant biomarkers for Alzheimer’s, such as Amyloid beta. However, extracting CSF is an invasive and painful procedure.

Despite advancements in diagnostic techniques over recent years, many remain costly and impractical for widespread population screening. It's uncertain whether focusing solely on Amyloid beta is sufficient since other proteins, like Tau, also accumulate in the brains of individuals with and without cognitive impairments. The challenge remains to study protein accumulation across diverse populations without incurring exorbitant costs.

Section 1.2: The Promise of Blood Tests in Alzheimer’s Diagnosis

Currently, numerous pharmaceutical companies are developing blood tests to gauge the risk of Alzheimer’s disease. Some of these tests aim to quantify the presence of various plaques and proteins, particularly since many treatments targeting Amyloid beta have underperformed in clinical trials.

For instance, Eli Lilly has created antibodies to inhibit Tau deposition, another protein associated with Alzheimer’s. Fragments of these Tau plaques enter the bloodstream, leading to the discovery of phospho-tau217 (p-tau217), a promising biomarker.

Research indicates that blood tests could accurately distinguish between different neurodegenerative diseases, achieving results comparable to traditional imaging and CSF tests. However, these blood tests are primarily designed to identify individuals who may require imaging for confirmation.

Qualterix has introduced a different blood test focused on another variant of the Tau protein, aimed at predicting asymptomatic Alzheimer’s cases. This innovation will facilitate the recruitment of high-risk individuals for clinical trials aimed at halting the disease's progression.

Despite these advancements, such tests are not yet broadly accessible to patients. C2N has pioneered a blood test enabling clinicians to diagnose early Alzheimer’s symptoms by targeting Amyloid beta fragments. While the test costs around $1250, eligible patients may pay significantly less, making it more accessible. C2N stands out as the first company to offer a widely available diagnostic test for Alzheimer’s.

With the introduction of blood tests, we can begin to monitor the accumulation of proteins linked to Alzheimer’s over time. This will enhance our understanding of the role these proteins play in brain health and help us assess the viability of targeting them in treatment strategies.