What is ALZ-NET, and what does it do with patient data?

What it is

ALZ-NET - the Alzheimer's Network for Treatment and Diagnostics - is a patient registry. That is a clinical word for a structured database that captures information about patients who share a defined condition or who are receiving a defined treatment, so that the information can be aggregated, analysed, and used to answer questions that individual clinical trials do not cover.

ALZ-NET was built specifically around the arrival of anti-amyloid antibody therapy in early Alzheimer's disease. It captures real-world clinical data on people receiving lecanemab, donanemab, and related treatments as they are used in routine care.

It is run collaboratively by the American College of Radiology and the Alzheimer's Association, with input from clinical and scientific advisors. Participating health systems and clinical practices enrol and submit data on behalf of their consenting patients.

Why it exists

Clinical trials answer specific, narrow questions about a treatment in highly selected populations over fixed timelines. They do not, and cannot, answer the full set of real-world questions that accumulate once a treatment reaches routine use - things like: how often are adverse events actually occurring in the broader eligible population, how are clinicians using the treatment across different settings, how are patients doing months and years into therapy, and how do outcomes vary across subgroups.

The arrival of anti-amyloid therapy made these questions acute. Both the FDA label and CMS's coverage-with-evidence-development framework build in the expectation that real-world data will be collected, analysed, and used to refine the treatment paradigm as the field accumulates experience. ALZ-NET is the practical mechanism.

How it connects to Medicare

In the US, Medicare coverage of anti-amyloid antibodies is structured through CMS's coverage-with-evidence-development framework - a way of paying for a treatment on the condition that defined clinical data is collected. For a plain-language overview, see our explainer on coverage with evidence development.

ALZ-NET is the main qualifying registry under that framework. When a Medicare beneficiary receives anti-amyloid therapy at a participating site, their care is delivered normally; at the same time, clinical data - demographics, diagnostic biomarker results, APOE genotype, treatment course, ARIA and other safety events, cognitive and functional outcomes - is submitted to the registry on a defined schedule.

The patient does not need to join ALZ-NET directly. Participation happens at the practice level, via the informed-consent process that the site uses.

What data gets captured

The registry is designed to capture enough information to answer the questions CMS and the field need answered. In broad terms:

• Before treatment: demographics, clinical history, cognitive and functional baseline measures, diagnostic biomarker confirmation (amyloid PET, CSF, or plasma), APOE genotype, baseline MRI findings.
• During treatment: dose, infusion dates, treatment pauses or adjustments, monitoring MRI findings, any ARIA events (imaging findings, symptoms, severity, management), other adverse events, cognitive and functional follow-up.
• After treatment course: reason for discontinuation (if any), subsequent treatment decisions, longer-term outcomes where available.

Data is structured, coded, and de-identified for research use.

What happens with the data

Aggregated ALZ-NET data feeds into several downstream uses:

• Post-marketing safety surveillance - real-world ARIA frequencies and serious-event profiles, reported across participating sites. The early readouts have broadly matched trial estimates, which we cover in our Signal on real-world ARIA rates from registries.
• Future Medicare coverage decisions - CMS can use accumulated registry data to refine the conditions of coverage, narrow or broaden eligibility criteria, or transition from the CED framework to ordinary coverage.
• Peer-reviewed research - investigators can propose analyses of the dataset under a governance framework, producing publications that inform the broader field.
• Quality improvement - participating health systems can benchmark their own practice against aggregate patterns.

For the strategic frame of what this is doing to Alzheimer's intelligence more broadly, see our Insight on real-world data as the binding signal.

What it is not

ALZ-NET is not a clinical trial. There is no treatment arm or control arm, no randomisation, no fixed study hypothesis. It is an observational dataset designed to capture how treatment actually unfolds in real clinical use. That distinction matters when interpreting ALZ-NET-derived findings: they are informative about routine practice, but they do not carry the causal inference strength of a randomised comparison.

It is also not an advocacy or patient-support organisation - though the Alzheimer's Association, which has patient-support functions, is one of the two governing bodies. Those are separate activities at the same organisation.

What this means in practice

If a patient is receiving anti-amyloid therapy under Medicare at a participating site, some of their clinical information is being captured in ALZ-NET. The care is delivered normally; the registry layer runs behind it. The patient's consent is part of the informed-consent process at the participating site; patients can ask their clinician for the specifics of what is captured and how.

If a patient is not on Medicare, or is being treated at a site that does not participate in ALZ-NET, their data is not in the registry. Most commercial-payer patients and many community-practice patients fall in this category, which creates an uneven national evidence base - one of the ongoing structural points about how the real-world picture of anti-amyloid therapy is forming.

This page is a plain-language primer. It is not medical advice, and it is not a substitute for the specific informed-consent conversation a patient has with their clinician and participating site.