Home › Research › Treatments
Amyloid and Tau Cerebrospinal Fluid Biomarker Normalization in a Patient with Alzheimer’s Disease treated with Lecanemab: A Case Report
Marciniak-Agra K, Devi G.. Research Square, 2026-08-25
Topic: Plasma and spinal-fluid biomarkers
Objectives To report a case of normalization of cerebrospinal fluid (CSF) amyloid and tau biomarkers following lecanemab therapy in a patient with Alzheimer’s disease (AD). Methods A woman (APOEε3/ε4) was diagnosed with AD after clinical, neurocognitive, and CSF evaluation. She received 10mg/kg of intravenous lecanemab for 20 months. She underwent serial annual structured cognitive testing and post-treatment CSF evaluation. She was concurrently treated with donepezil, memantine, and off-label repetitive transcranial magnetic stimulation. Results CSF Aβ42 rose from 526.0 to 1053.0 pg/mL (+ 100.2%), total tau (t-tau) fell from 578.2 to 278.0 pg/mL(-51.9%), and phosphorylated tau181 (p-tau181) fell from 90.8 to 23.1 pg/mL(-74.6%). Her performance remained stable on serial neurocognitive evaluations. Discussion While lecanemab is known to clear amyloid plaque and is associated with downstream reductions in tau, this is the first reported case, to our knowledge, of normalization of both amyloid and tau CSF biomarkers after anti-amyloid monoclonal antibody therapy.
Key findings
- Results CSF Aβ42 rose from 526.0 to 1053.0 pg/mL (+ 100.2%), total tau (t-tau) fell from 578.2 to 278.0 pg/mL(-51.9%), and phosphorylated tau181 (p-tau181) fell from 90.8 to 23.1 pg/mL(-74.6%).
- Discussion While lecanemab is known to clear amyloid plaque and is associated with downstream reductions in tau, this is the first reported case, to our knowledge, of normalization of both amyloid and tau CSF biomarkers after anti-amyloid monoclonal antibody therapy.
New to this subject? Start with our plain-English guide: Treatments →
Study details
- Effect size100.2%; 51.9%; 74.6%
- Evidence strengthLow
How this study scored 16/100
Preprint — not yet peer-reviewed. It scored 24 on the same rubric, but non-peer-reviewed sources are capped at 16, so it shows as 16. Scored zero for study design, sample size, studied in people and randomised / blinded because the record does not state it. We have no data on times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 15 of the 62 points we could judge it on, which is 24 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 2 / 10 | Tier 4 — not a peer-reviewed journal (Research Square) |
| Journal's citation record | 0 / 4 | Not a journal article, so the journal's record does not count |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 4 / 10 | Preprint — not yet peer-reviewed. Hosted on a preprint server. |
| How recent | 5 / 5 | 2026 — within 1 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 15 / 62 | Scored on 12 of 20 parts. We have no data for the rest, so they are left out: 15 of the 62 points we could judge it on is 24 out of 100. |
| Total | 24 / 100 | Capped to 16 because this is not a peer-reviewed article. |
What each of these 20 components measures, and what this score is not →
Read the original
Free copy unknown: no free-copy check has an answer for this record yet. That does not mean it is paywalled.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Marciniak-Agra, K., & Devi, G. (2026). Amyloid and Tau Cerebrospinal Fluid Biomarker Normalization in a Patient with Alzheimer’s Disease treated with Lecanemab: A Case Report. Research Square. https://doi.org/10.21203/rs.3.rs-10778388/v1
Vancouver
Marciniak-Agra K, Devi G. Amyloid and Tau Cerebrospinal Fluid Biomarker Normalization in a Patient with Alzheimer’s Disease treated with Lecanemab: A Case Report. Research Square. 2026. doi:10.21203/rs.3.rs-10778388/v1.
BibTeX
@article{marciniakagra2026-1d9e787e,
author = {Marciniak-Agra, K. and Devi, G.},
title = {{Amyloid and Tau Cerebrospinal Fluid Biomarker Normalization in a Patient with Alzheimer’s Disease treated with Lecanemab: A Case Report}},
journal = {Research Square},
year = {2026},
doi = {10.21203/rs.3.rs-10778388/v1},
url = {https://doi.org/10.21203/rs.3.rs-10778388/v1}
}
Related studies in Treatments
Also tagged “blood-based”
698 studies in the library carry the topic tag “blood-based”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 698 tagged studies.