Tauklarify imaging is a brain PET scan that maps tau tangles in adults with cognitive impairment being evaluated for Alzheimer's disease. A positive result means readers saw the tau pattern; a negative result means they did not, and clinics interpret either result with other tests. Tauklarify is florquinitau F 18 injection, a radioactive tracer given by vein before PET to bind clumped tau.
Lantheus investor relations announced FDA approval on Aug. 14, 2026 for this use in the FDA approval notice. Tau tangles are twisted tau fibers inside brain cells that disrupt memory circuits.
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 does a positive or negative result mean?
- How consistent are readings?
- When should a result need more testing?
- Who is this scan not built for?
- What should you expect on scan day?
What does a positive or negative result mean?
Trained readers rate signal pattern and strength in the medial temporal lobe, the memory area, and the neocortex, the outer thinking layer. Tangles confined to the medial temporal lobe alone count as positive. NeurologyLive describes this read method in its scan-reading summary. A positive means the tau pattern was present in expected areas, which supports Alzheimer evaluation but does not alone diagnose it.
A negative means no such pattern was seen, which makes widespread tangles less likely but does not rule out early disease. Your doctor weighs the scan with memory tests, function history, and often amyloid results. For example, a person with mild impairment and a medial-temporal-only positive still meets the positive definition. The same scan in a person with strong frontotemporal symptoms needs a different workup. Location and clinical picture matter together.
How consistent are readings?
Pharmacy Times reports two blinded-read studies with 617 scans and five readers in its approval coverage. Positive agreement ranged 68%-88% and negative agreement ranged 93%-99%. Interreader reliability was strong, with Fleiss kappa about 0.86-0.92.
High negative agreement means readers rarely disagree on a clear negative. The wider positive range means early or faint uptake can divide readers. If your report notes faint or borderline uptake, ask whether a second read occurred.
When should a result need more testing?
A negative scan does not necessarily exclude tau pathology, and a positive scan does not necessarily confirm it at autopsy. NeurologyLive notes performance may be lower at earlier pathologic stages. Add evaluation when the scan and symptoms disagree.
Use mismatch as a trigger for next steps, not as a final answer. These questions help clarify an uncertain result: Early tangles are hardest to image, so follow-up matters most when memory decline is new. Write down symptom onset, pace, and daily impact before you return.
- What stage or burden does my pattern suggest, if any?
- Which other tests — memory testing, blood, spinal fluid, or amyloid imaging — clarify it?
- Should we schedule clinical follow-up to track change?
Who is this scan not built for?
Safety and effectiveness are not established for non-Alzheimer tau diseases. Lantheus lists frontotemporal dementia, progressive supranuclear palsy, and other non-AD disorders as limits. A tau pattern from those diseases may not show the same way.
Tauklarify is the second FDA-cleared tau PET agent after Tauvid from 2020. Being Patient reports a Lancet head-to-head study where MK-6240 found tangles earlier and separated AD impairment better, AUC 0.93 versus 0.86. That edge matters for memory-clinic referrals, not for FTD or PSP evaluation.
What should you expect on scan day?
In 1,734 subjects, Pharmacy Times reports headache in 0.7% and nausea in 0.2%. Labeling advises radiation precautions plus hydration and voiding after injection. It also advises avoiding CYP1A2 inducers and smoking for 7 days and pausing lactation for 4 hours.
Plan with simple steps before you go. Tell staff about smoking, medicines, possible pregnancy, and breastfeeding. Arrange hydration, bathroom breaks, and a ride if the clinic advises one.
You Might Also Like
- Tauklarify Tau PET vs Alzheimer’s Blood Tests in 2026: How Memory Clinic Patients Can Compare Testing Options
- PrecivityAD2 as an Adjunct to a 2026 Alzheimer’s Assessment: Result Interpretation Questions for Memory Clinic Patients
- FDA’s 2026 PrecivityAD2 Alzheimer’s Blood Test Clearance: Result Interpretation Questions for Memory Clinic Patients
