Original Medicare has no national policy that names the Lumipulse pTau217 blood test, so coverage is decided case by case rather than guaranteed. Part B can pay for it as a diagnostic lab test when a doctor orders it for a patient who already has memory or thinking symptoms, but some Medicare Advantage plans now list it as covered outright while others leave it to plan medical policy. The Lumipulse G pTau217/β-Amyloid 1-42 Plasma Ratio is a blood test that measures two proteins tied to Alzheimer's brain changes. It is meant to help a doctor decide whether amyloid plaques are likely present in someone already being evaluated for cognitive decline — not to tell a healthy person what is coming.
Medical information disclaimer: This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a physician or other qualified health professional about symptoms, medications, tests, or treatment decisions.
Official resources:
- Check eligibility on NIH’s official study page — Use this page to check the study’s participation requirements.
- Read the official notice from FDA — Use this primary source to verify the official announcement.
Table of Contents
- What the test is and who it is cleared for
- How Medicare's rules actually apply
- What it costs if Medicare does not pay
- Where coverage already exists
- Steps to take before the blood draw
- Frequently Asked Questions
What the test is and who it is cleared for
The FDA cleared the Fujirebio test on May 16, 2025 under 510(k) K242706, making it the first blood-based in vitro diagnostic cleared to help diagnose Alzheimer's disease. The cleared population is narrow: adults 55 and older who are already showing signs and symptoms of cognitive decline. The clearance data came from 499 cognitively impaired adults. Among those with a positive plasma result, 91.7% were confirmed amyloid-positive by PET imaging or spinal fluid testing, and 97.3% of negative results matched the absence of amyloid. Fewer than 20% of results were indeterminate — neither positive nor negative.
The FDA is explicit that this is not a screening test and not a standalone diagnosis. A positive result supports a clinical picture built from history, examination and cognitive testing; it does not replace them. That framing matters for coverage, because payers follow the cleared indication closely. Labcorp began offering the FDA-cleared version nationwide on August 18, 2025, replacing the laboratory-developed test it had run since April 2025. Blood can be drawn at a doctor's office or at more than 2,200 Labcorp patient service centers.
How Medicare's rules actually apply
Medicare Part B covers diagnostic clinical laboratory tests when a physician or qualified non-physician practitioner orders them and they are medically necessary. Medicare's own coverage page for diagnostic lab tests says beneficiaries usually pay nothing for them when the lab accepts assignment. That general rule is the pathway any payment for this test would travel. The gap is that no national coverage determination names Alzheimer's blood biomarkers.
A UnitedHealthcare Medicare Advantage laboratory policy, M-LAB22, states plainly that "Medicare coverage guidance is not available for the testing of biochemical markers of Alzheimer's disease". When no national rule exists, the decision falls to Medicare Administrative Contractors and to individual plan medical policy. A 2025 stakeholder assessment published in the *Journal of Alzheimer's Disease* found that neither public nor private payers currently cover Alzheimer's blood biomarker tests as a class. The same analysis notes that CMS does not pay for testing in people without symptoms, because testing an asymptomatic person counts as screening — a category Part B does not reach here.
What it costs if Medicare does not pay
Patients have been billed directly while coverage stays unsettled. A JAMA analysis of payer considerations for Alzheimer's blood biomarkers cites a $1,450 list price for one marketed test, which is the order of magnitude to plan around if a claim is denied. Billing codes are a second, quieter source of denials.
Labcorp lists the Lumipulse ratio under standard chemistry codes 82234 and 84393, while Anthem's laboratory policy expects the unlisted multianalyte code 81599 for the same panel. A claim that arrives under a code the payer's policy does not recognize can be rejected on paperwork grounds even when the clinical case is sound. Before the draw, it is worth asking the ordering office which codes they will submit and whether they have checked the patient's specific plan policy. A ten-minute call is cheaper than appealing a four-figure bill.
Where coverage already exists
Medicare Advantage is moving faster than Original Medicare. A BlueCross BlueShield of Tennessee reimbursement policy dated September 18, 2026, administered with Avalon, lists the FDA-cleared Lumipulse test as meeting coverage criteria for members with suspected Alzheimer's disease or mild cognitive impairment. Original Medicare already pays for the other way to confirm amyloid. CMS retired national coverage determination 220.6.20 effective October 13, 2023, which ended coverage-with-evidence-development and the once-per-lifetime limit on amyloid PET scans, handing those decisions to the Medicare Administrative Contractors.
So a patient refused the blood test may still have a covered imaging route to the same question. That contrast is the practical point. The blood draw is cheaper and far easier than a PET scan, but the scan has the clearer coverage history. Which one gets paid for can depend more on plan paperwork than on clinical logic.
Steps to take before the blood draw
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- Confirm symptoms are documented. The cleared indication requires existing signs of cognitive decline in someone 55 or older; testing without documented symptoms reads as screening and will not be covered.
- Ask the plan directly. Call the number on the Medicare Advantage card and ask whether the plan's medical policy covers biochemical markers of Alzheimer's disease, and whether prior authorization is required.
- Ask which CPT codes the lab will bill, given the 82234/84393 versus 81599 split, and whether those match what the plan expects.
- Get the expected self-pay price in writing from the lab before the draw, so a denial does not arrive as a surprise.
- Ask the clinician what changes based on the result. If the answer does not alter treatment, referral or planning, the test may be worth deferring.
Frequently Asked Questions
Can I get this test if I have no memory symptoms?
Not under Medicare. The FDA cleared it only for adults 55 and older already showing signs of cognitive decline, and CMS does not pay for biomarker testing in asymptomatic people because that counts as screening.
Does a positive result mean I have Alzheimer's?
No. The FDA states the test is not a standalone diagnostic. A positive result indicates amyloid is likely present and supports a diagnosis a clinician builds from history, examination and cognitive testing.
What does an indeterminate result mean?
It means the ratio fell between the positive and negative thresholds. In the clearance study, under 20% of results landed there, and those patients generally need imaging or spinal fluid testing to settle the question.
If the blood test is denied, is a PET scan still an option?
Often, yes. CMS retired the national coverage determination restricting amyloid PET on October 13, 2023, including the once-per-lifetime limit, so the contractor serving your region now decides those claims.
