Executive summary
The FDA launched its new Adverse Event Monitoring System (AEMS) on March 11, 2026, which will consolidate six legacy adverse event databases into a single, real-time platform that fundamentally transforms how plaintiff attorneys research and utilize safety data in drug and device litigation.
- AEMS has already replaced FAERS, VAERS, and AERS, with plans to consolidate the remaining systems for medical devices (MAUDE), human foods (HFCS), and tobacco products (CTPAE) by the end of May 2026.
- Adverse event data is now published in real time rather than on a quarterly schedule, eliminating months of delay that previously forced attorneys to rely on FOIA requests.
- A unified, cross-product dashboard allows safety signal research across drugs, biologics, vaccines, and devices from a single interface.
The old patchwork and its limitations
For decades, the FDA operated six separate adverse event reporting systems, each designed for a different product category with its own interface, search logic, and data release schedule. FAERS covered drugs and biologics. VAERS handled vaccines. MAUDE tracked medical devices. Additional systems existed for animal drugs, human foods, and tobacco products. (FDA, FDA Adverse Event Monitoring System (AEMS))
For plaintiff attorneys, this fragmentation posed real challenges. Researching a drug that was often used alongside a medical device meant searching multiple databases with inconsistent naming conventions and varying data structures. The FAERS Public Dashboard, the most widely used system, was updated only quarterly until August 2025, meaning the most recent adverse event reports could be several months old by the time they were made publicly available. (Fierce Pharma, “FDA Rolls Out New Streamlined Adverse Event Monitoring System”) That delay led to a high volume of Freedom of Information Act requests from those seeking more up-to-date safety information. (Pharmaceutical Commerce, “FDA Vows Improved Adverse Event Reporting With AEMS”)
Together, these seven databases cost the FDA about $37 million annually to operate. (The ASCO Post, “FDA Consolidates Systems Into One Cohesive Adverse Event Monitoring Tool”)
What AEMS changes
The new system is more than just a minor interface update. AEMS marks the most significant transformation of the FDA’s post-market surveillance infrastructure in the agency’s history, according to FDA Chief AI Officer Jeremy Walsh. (CIDRAP, “FDA Announces AEMS, New Adverse-Event Database to Replace VAERS”) The platform merges all legacy systems into a single interactive public dashboard, with several features that directly benefit litigation research.
First, adverse event data is now published daily, nearly in real-time, instead of quarterly. (FDA, AEMS Public Dashboard) This alone changes how quickly cases are processed. An attorney assessing a potential mass tort no longer must wait months or submit a FOIA request to get the latest reports.
Second, the unified dashboard enables cross-product searching. Safety signals spanning multiple product categories, such as a biologic and a companion device, can now be identified with a single query. In the past, recognizing those patterns required manually correlating data from separate databases with different structures.
Third, the FDA has announced upgraded application program interfaces (APIs) and data analytics tools, including AI-assisted features for signal detection and data processing. (The ASCO Post, “FDA Consolidates Systems Into One Cohesive Adverse Event Monitoring Tool”) The platform also includes historical data going back to 1968, giving attorneys a comprehensive longitudinal dataset for trend analysis. (FDA, AEMS Public Dashboard)
Strategic advantages for case development
The practical implications for plaintiff attorneys are significant. Access to real-time data shortens the timeline for early case assessment. When a new safety concern arises, attorneys can now track the volume and types of adverse event reports as they are submitted, rather than waiting for the next quarterly data release. This earlier insight can guide decisions about case viability, client intake, and expert retention.
The cross-product search feature is especially useful for combination product litigation and cases involving polypharmacy. A single AEMS query can identify adverse event patterns related to a drug and its delivery device or among multiple co-prescribed medications. While this analysis was technically possible with the old system, it required significant manual effort across separate databases.
The reduction in reliance on FOIA is also notable. Under the old system, getting timely adverse event data often required formal information requests that could take weeks or months to process. The FDA has said that real-time publication is expected to greatly decrease the number of such requests because the information will already be available to the public. (MedCity News, “FDA Transparency Push Expands to Monitoring Safety of Vaccines and Other Regulated Products”)
Understanding the disclaimers
Plaintiff attorneys should also be aware that AEMS includes prominent data limitation language. The landing page for the public dashboard states:
While the FDA AEMS Public Dashboard offers stakeholders many more ways of searching for and organizing data on adverse events reported to the FDA for many drug and biologic products, there remain limitations to the data. For example, while AEMS contains reports on a particular drug or biologic, this does not mean that the drug or biologic caused the adverse event. Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic. Some additional limitations to note include:
- Duplicate and incomplete reports are in the system: There are many instances of duplicative reports and some reports do not contain all the necessary information.
- Existence of a report does not establish causation: For any given report, there is no certainty that a suspected drug caused the event. While consumers and healthcare professionals are encouraged to report adverse events, the event may have been related to the underlying disease being treated, or caused by some other drug being taken concurrently, or occurred for other reasons. The information in these reports reflects only the reporter’s observations and opinions.
- Information in reports has not been verified: Submission of a report does not mean that the information included in it has been medically confirmed nor it is an admission from the reporter that the drug caused or contributed the event.
- Rates of occurrence cannot be established with reports: The information in these reports cannot be used to estimate the incidence (occurrence rates) of the events reported.
- Patients should talk to their doctor before stopping or changing how they take their medications.
Source: fda.gov
These disclaimers will likely figure prominently in Defense counsel challenges to the opinions of Plaintiff experts that rely on AEMS data. The best approach is to view adverse event data as part of a larger body of evidence rather than the sole basis for causation opinions. Adverse event reports are still useful for identifying safety signals, showing that a manufacturer was aware of reported issues, and revealing patterns that merit further scientific study.
Preparing for the transition
The transition to AEMS is happening now. Litigation teams that update their research workflows early will be best positioned to leverage the new system’s capabilities. This includes familiarizing paralegals and litigation support staff with the updated dashboard interface, revising any internal protocols that reference legacy system names like FAERS or MAUDE, and recognizing that the compressed data publication timeline may speed up defense counsel’s access to the same information (although of course, defense counsel should already have it for reports submitted by their clients). The new real-time reporting environment increases the likelihood that significant probative evidence could become available at awkward junctures, such as just before the disclosure of an expert report or even during trial.