A flurry of news for Alzheimer diagnostics, and we're closing in on the international Alzheimer conference in Toronto, AAIC-26.
Two longstanding organizations, the Michael J Fox Foundation [Parkinson's] and te Alzheimer Drug Discovery Foundation, ADDF, are partnering, initially with $5M, to develop noninvasive testing. This $5M is part of a broader $50M effort of the ADDF to advance "next generation tests." 360Dx here.
See an article in Science, 12 May 2026, writing
- Most dementia patients have multiple brain diseases. How should they be treated? Growing awareness of “copathology” inspires new diagnostic tests and clinical trials.
- See SIDEBAR, below.
Amprion receives funding from Decathlon Partners as growth capital for both Parkinson's and Alzheimer's biomarkers. Here.
Anthem issues coverage for C2N multimodal PrecivityAD2 blood test. Press.
See the actual Anthem policy, Testing for biochemical markers in Alzheimer's disease, LAB.00046. There is also more general coverage for FDA approved p217 tau tests. It looks like effective date October 1.
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Blood Biomarkers Advance as Payer Policies Evolve
One way to read this week's news is against the backdrop of Medicare's decade-long evolution on amyloid PET imaging.
In 2013, CMS adopted one of its most restrictive coverage policies for any diagnostic technology, limiting amyloid PET almost entirely to Coverage with Evidence Development studies. The resulting IDEAS study, led by investigators at UCSF, demonstrated that PET frequently changed physicians' diagnoses and management plans but did not achieve its harder endpoint of reducing hospitalizations or emergency department visits. Nevertheless, much of the public messaging emphasized the management changes, while the more clinically important utilization results received less attention.
The landscape looks very different today. Anti-amyloid therapies have transformed biomarkers from primarily diagnostic tools into treatment-selection tools. In 2023, CMS withdrew its National Coverage Determination for amyloid PET altogether, leaving coverage decisions to the Medicare Administrative Contractors. Ironically, Medicare moved from one of its most tightly controlled diagnostic policies to one with remarkably little published contractor guidance.
Against that backdrop, Anthem's new medical policy is noteworthy. Rather than simply embracing every new blood test, Anthem has articulated a detailed clinical framework for both cerebrospinal fluid biomarkers and blood-based biomarkers. Blood tests are covered only in symptomatic patients after a standard diagnostic evaluation and only when results are expected to influence clinical management. The policy also recognizes FDA-cleared plasma assays as well as validated p-tau217 methodologies and explicitly positions blood testing as a triage tool that may reduce the need for PET imaging or lumbar puncture in selected patients.
Perhaps the greatest irony is institutional. Medicare currently has almost no publicly articulated coverage framework for amyloid PET beyond its general "reasonable and necessary" authority, while Anthem has published a detailed 20-page policy describing how blood biomarkers, CSF biomarkers, and PET imaging fit together in modern Alzheimer's diagnosis.
- Twenty years ago, observers might have expected Medicare to provide the more explicit national framework.
- In 2026, at least in this area, the commercial payer has become the more transparent rule-maker.
Taken together, the Medicare and Anthem stories illustrate how rapidly Alzheimer's diagnostics are evolving. A decade ago, the central reimbursement question was whether amyloid biomarkers should be covered at all. Today, the question has shifted to which biomarker should be used first, in which patients, and when more expensive confirmatory testing can safely be avoided.
Sidebar:
What Anthem's New Alzheimer's Biomarker Policy Covers
Anthem's revised medical policy (LAB.00046), effective October 1, 2026, creates a structured coverage pathway for both cerebrospinal fluid (CSF) biomarkers and blood-based biomarkers in the evaluation of suspected Alzheimer's disease. Unlike a product-specific coverage decision, the policy establishes clinical criteria that apply across technologies.
General eligibility requirements
Coverage begins with three overarching requirements:
The patient must have measurable mild cognitive impairment or dementia consistent with possible Alzheimer's disease, with an insidious, progressive course.
A standard diagnostic evaluation must already have been completed, including history and neurological examination, cognitive testing, and evaluation for reversible causes such as vitamin B12 deficiency, thyroid disease, depression, or medication effects.
The biomarker result must be expected to influence clinical management—for example, distinguishing Alzheimer's disease from other dementias, resolving conflicting clinical information, increasing diagnostic confidence, or determining eligibility for amyloid-targeting therapy.
CSF biomarkers
Coverage includes established cerebrospinal fluid biomarkers, including:
Aβ42 or the Aβ42/Aβ40 ratio;
phosphorylated tau (p-tau181 or p-tau217);
total tau; and
tau/amyloid ratio combinations.
Blood-based biomarkers
Blood testing is covered when:
the patient is age 50 years or older;
the assay is FDA-cleared or FDA-approved, or measures p-tau217 (or %p-tau217); and
testing is used to:
triage whether PET imaging or CSF testing is needed;
substitute for CSF when lumbar puncture is impractical or contraindicated; or
assist referral and specialty evaluation.
What is not covered
The policy excludes:
testing asymptomatic individuals, including those tested solely because of family history;
testing when another diagnosis already explains the cognitive impairment; and
repeat testing that is unlikely to change management.
How Anthem views blood tests
The policy stops short of treating blood biomarkers as universal replacements for PET or CSF. Instead, it describes them as clinically useful tools within a broader diagnostic pathway. The accompanying evidence review repeatedly notes that positive blood-test results may still require confirmation by PET imaging or CSF analysis, while negative tests may reduce the need for further evaluation in appropriate patients. It also notes that confirmation of amyloid pathology remains important when considering anti-amyloid therapies.
Overall, Anthem's approach reflects the direction increasingly advocated by Alzheimer's specialists: blood biomarkers become the first step in a staged diagnostic algorithm, while PET and CSF remain the reference standards for selected patients and high-stakes treatment decisions.
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SIDEBAR:
The SCIENCE article on Co-Pathology
Copathology: Dementia increasingly looks less like a set of cleanly separated diseases and more like overlapping mixtures of abnormal proteins. Autopsy studies show that many patients diagnosed with Alzheimer’s also have alpha-synuclein, TDP-43, vascular injury, or other pathologies, while many Parkinson’s patients with dementia also harbor amyloid and tau.
These combinations may help explain why symptoms, biomarker results, rates of decline, and treatment responses often fail to line up neatly. Researchers are therefore developing blood and spinal-fluid tests that measure several pathologies at once, rather than asking only whether a patient is “amyloid positive.” The immediate clinical problem is that diagnostics are advancing faster than treatment: physicians may soon be able to describe a patient as having a particular mixture of Alzheimer, Lewy body, vascular, and TDP-43 disease, while having drugs for only one component.
An upcoming donanemab trial in patients with both Lewy body dementia and high amyloid will test whether treating one pathology can still help in a mixed disease state.
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Nerd Note: PAMA
ACLA and others introduced general Category I biomarkers for Alzheimer's disease over the last 3 years. Most or all of these will be up for re-pricing under PAMA this summer.