Tauklarify is a new PET imaging agent for tau protein tangles in the brain, and blood tests like PrecivityAD2 are a cheaper, simpler alternative for the amyloid side of Alzheimer's diagnosis — but they answer different questions and aren't yet equally available. The FDA approved Lantheus's Tauklarify (florquinitau F-18) on August 14, 2026, for adults with cognitive impairment being evaluated for Alzheimer's disease, while the FDA cleared C2N's PrecivityAD2 blood test on August 20, 2026, for adults as young as 40 with symptoms of cognitive impairment. For someone with mild cognitive impairment (MCI) — a stage where thinking or memory problems are noticeable but don't yet block daily independence — the practical difference right now is access. A blood draw can happen at most clinics today; a Tauklarify scan depends on where and when it becomes available, and on what a specific insurer or Medicare contractor decides to pay for.
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.
Table of Contents
- What Tauklarify Actually Detects
- Why a Tauklarify Scan May Not Be Available Yet
- What a PrecivityAD2 Blood Test Can and Can't Tell You
- What Each Option Costs, and Who Pays
- Questions Worth Asking a Clinician Right Now
- Frequently Asked Questions
What Tauklarify Actually Detects
Tauklarify is a radioactive tracer injected before a PET scan. It binds to tau neurofibrillary tangles, a protein buildup inside brain cells that is one of the two hallmark changes of Alzheimer's disease, alongside amyloid plaques. The scan shows a clinician where and how much tangle pathology is present. The FDA based its approval on two blinded-read studies spanning more than 500 subjects across three trials, including people with mild cognitive impairment.
Positive percent agreement — how often the scan correctly flagged tangle pathology that was confirmed by other means — ranged from roughly 68% to 88%, and negative percent agreement ranged from 93% to 99%, depending on the study, according to Healio's coverage of the approval data. Headache was the main side effect, occurring in about 0.7% of the 1,734 subjects studied. Tauklarify's label is specific about what it does not cover: the FDA has not established that it works for evaluating tau buildup from conditions other than Alzheimer's, such as other tauopathies, according to an SNMMI summary of the approval. It is only the second tau PET tracer ever approved in the US, after Lilly's Tauvid in 2020.
Why a Tauklarify Scan May Not Be Available Yet
Approval is not the same as availability. As of the approval date, Lantheus had not announced a commercial launch timeline or a price, stating only that it was still assessing "the most appropriate path toward broader commercial availability," according to coverage from Applied Radiology.
That means a clinician cannot necessarily order a Tauklarify scan today even if a patient wants one. The practical first question for a patient with MCI is whether their local PET imaging center or memory clinic has received the tracer at all — not whether it's covered, since it may not yet be orderable in most of the country.
What a PrecivityAD2 Blood Test Can and Can't Tell You
PrecivityAD2 is a blood test that estimates the likelihood of amyloid plaque buildup, the other hallmark Alzheimer's protein, rather than tau tangles. The FDA's clearance of it on August 20, 2026, extended eligibility down to age 40, younger than any prior FDA-cleared Alzheimer's blood test, for adults showing signs or symptoms of cognitive impairment. In C2N's 1,142-participant validation study, a positive result carried a 97.6% positive predictive value for amyloid pathology, and a negative result carried a 93.1% negative predictive value, according to AJMC's report on the clearance.
Those numbers describe how often the test's call matches amyloid status confirmed by other testing — they are not a diagnosis on their own. The company and reporting describe the test as a complement to clinical evaluation, not a replacement for it. Because PrecivityAD2 measures amyloid and Tauklarify measures tau, they are not interchangeable: a clinician evaluating MCI may use one, the other, or both, depending on which protein pathway needs to be confirmed and what each can help rule in or out.
What Each Option Costs, and Who Pays
Medicare coverage for amyloid PET scans changed in a way that also affects the landscape Tauklarify enters. CMS removed the national coverage determination that previously limited amyloid PET to one scan per lifetime under "coverage with evidence development," leaving coverage decisions for Alzheimer's-related PET scans to local Medicare Administrative Contractors, according to Applied Radiology's coverage of the CMS decision. That means Tauklarify's eventual coverage status will likely also be decided locally rather than nationally.
An ISPOR analysis of Medicare claims after that change found insured Medicare beneficiaries paid about $203 out of pocket on average for one amyloid PET scan, while self-pay list prices for PET imaging generally run from roughly $1,000 to $7,000 depending on the facility. For blood testing, C2N's earlier PrecivityAD test listed self-pay prices between about $1,250 and $1,450, though the company's financial assistance program can bring that down to between $25 and $400 for qualifying patients, according to 360Dx/UCHealth reporting. That test has historically been available only on a self-pay basis, outside insurance billing. Tauklarify's own price has not been announced, so a patient or caregiver comparing costs today is comparing an established price range for PET generally against a test with no published price at all.
- A Medicare-insured amyloid PET scan: roughly $203 out of pocket on average.
- A self-pay PET scan: roughly $1,000-$7,000 depending on the facility.
- A self-pay blood test (PrecivityAD): roughly $1,250-$1,450 list, or $25-$400 with financial assistance.
Questions Worth Asking a Clinician Right Now
Given where each option stands, a person with MCI or their caregiver has three concrete things to ask a neurologist or memory clinic, rather than assuming either option is simply "available": None of these questions have a single national answer in late 2026 — coverage and availability both depend on the specific clinic, insurer, and region involved, so asking directly is the only way to get a current answer for a specific patient.
- Can this clinic or an affiliated imaging center order Tauklarify yet, or is it still waiting on distribution from Lantheus?
- If a PET scan is ordered, has the local Medicare Administrative Contractor or private insurer confirmed what it covers, since there is no longer a single national rule?
- If a blood test is proposed instead, is it being used as a first screening step that may lead to further testing, or is it being treated as sufficient on its own?
Frequently Asked Questions
Is Tauklarify available at every imaging center now that it's FDA-approved?
Not necessarily. Lantheus had not announced a commercial launch date or price as of the approval, so availability depends on whether a specific center has received the tracer.
Can a blood test replace a PET scan for diagnosing Alzheimer's in someone with MCI?
PrecivityAD2 measures amyloid, not tau, and its maker and reporting describe it as a complement to clinical evaluation, not a stand-alone diagnosis.
Does Medicare cover amyloid PET scans without limit now?
CMS removed the national one-scan-per-lifetime rule, but coverage decisions now rest with local Medicare Administrative Contractors rather than a single national policy.
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