How did safety and ARIA monitoring protocols in Neurocept's trials compare with those submitted by Biogen and Eisai?

1. What regulators and companies have disclosed about lecanemab safety monitoring

Eisai and Biogen have presented long‑term efficacy and safety findings from their lecanemab program and explicitly described dosing and monitoring strategies tied to an 18‑month initiation period followed by maintenance dosing (10 mg/kg every four weeks or ongoing every two weeks) as part of their clinical program and regulatory submissions ^{[2] [1]}. Regulators in Europe and the EU’s CHMP repeatedly reviewed safety data in early 2025 and ultimately reiterated positive opinions or authorized use after safety reviews were completed ^{[3] [4] [5]}. Company releases emphasize safety profiles “consistent with prior studies” in post‑launch data and cite ongoing dialogue with regulators ^{[3] [1]}.

2. How lecanemab handled dosing and implied safety surveillance in trials

Eisai’s public materials stress a defined regimen: an initiation phase every two weeks for 18 months, then a transition to IV maintenance dosing every four weeks (or continuation every two weeks) and later development of subcutaneous maintenance options — a schema tied to their submissions to regulators and presentations at major conferences ^{[2] [1]}. These communications imply structured monitoring over years, with company statements and conference presentations used to report four‑year safety and efficacy data ^[1].

3. Regulatory action and focused safety reviews that shaped monitoring expectations

European regulators undertook specific safety reviews in early 2025, pausing for fresh safety information and then reaffirming a positive recommendation after considering new data ^{[3] [4] [6]}. The fact the CHMP and European Commission asked for and weighed additional safety information indicates that external regulators scrutinized the program’s safety monitoring and outcomes beyond what companies reported ^{[6] [7]}.

4. Public framing by Eisai/Biogen — emphasis, transparency and commercial timing

Eisai materials and Biogen investor releases repeatedly present lecanemab safety and long‑term data in positive terms and link safety elements to regulatory milestones (sBLA/BLA actions, PDUFA dates) and product innovations like a subcutaneous autoinjector, framing a safety profile “comparable” between IV and SC formulations ^{[8] [9] [1]}. Those releases serve both scientific and commercial narratives: reporting continued safety follow‑up while advancing new administration routes that the companies say reduce burden on patients and providers ^{[9] [10]}.

5. What the public record does not say about Neurocept

Available sources do not mention Neurocept, its trials, or any ARIA (amyloid‑related imaging abnormalities) monitoring protocols for Neurocept; therefore a side‑by‑side, evidence‑based comparison with Eisai/Biogen cannot be drawn from the current reporting. Any claim about Neurocept’s monitoring practices would be unsupported by the supplied materials (not found in current reporting).

6. What a fair comparison would require — the missing data

A meaningful comparison needs trial protocols or regulatory filings from Neurocept detailing ARIA monitoring frequency, imaging modalities used (MRI sequences and schedule), stopping rules for symptomatic or radiographic ARIA, and the size/phase of the trials. For lecanemab, the public record documents long‑term data, dosing regimens and regulatory safety reviews — the equivalent Neurocept documents are not present in these sources ^{[1] [2]}.

7. Bottom line and how to proceed to verify differences

From supplied reporting, Eisai and Biogen ran large, long‑term programs with an explicit initiation/maintenance dosing plan and attracted intense regulatory safety scrutiny in 2025 — facts documented by company releases and major news outlets ^{[1] [3] [4]}. To compare Neurocept’s ARIA monitoring you should request Neurocept’s clinical trial protocol, investigator brochure, or public regulatory filings; those documents are not included in the materials provided here (not found in current reporting).