The US Food and Drug Administration's (FDA) Sentinel database tracking medical product safety events is now an "integral part of routine safety surveillance," Janet Woodcock, director of the Center for Drug Evaluation and Research (CDER) at FDA said at the 8th Annual Sentinel Initiative Public Workshop in Washington, DC, Wednesday.
"We can, as of today, officially drop 'Mini' from the Sentinel title," she said, noting the progress made since the agency began transitioning from the Mini-Sentinel pilot project to an operational Sentinel system in 2014.
Despite the progress, Woodcock said that much of the work on Sentinel is yet to come, citing the need for additional infrastructure, data partners, methods validation and staff to fully operationalize the system.
Launched in 2008, the Sentinel initiative encompasses FDA's effort to meet obligations set by Congress in the 2007 Food and Drug Administration Amendments Act (FDAAA) to develop a system for active postmarket risk identification and analysis for medical products.
However, FDA hopes the Sentinel infrastructure will be used for much more than safety surveillance. One such use—the so-called Guardian system—is being developed by the agency "to actively gather information about the performance of regulated medical products."
Prior to the launch of the Sentinel initiative, FDA primarily relied on reporting systems such as the FDA Adverse Event Reporting System (FAERS), Manufacturer and User Facility Device Experience Database (MAUDE) and Vaccine Adverse Event Reporting System (VAERS), all of which depend on manufacturers, healthcare providers and patients to report adverse events related to healthcare products.
Instead, the Sentinel system, and its component parts, the Active Postmarket Risk Identification and Analysis (ARIA) system, Postmarket Rapid Immunization Safety Monitoring (PRISM) system and Blood Surveillance Continuous Active Network (BloodSCAN), are intended to complement FDA's passive reporting systems through active monitoring of regulated products.
Enhancements and Challenges
During her keynote address, Woodcock outlined some of the work FDA has done to transition the program out of its pilot phase.
In 2015, she said, FDA used Sentinel in 17 active protocol based assessments, and used the system's rapid query capabilities to run close to 2,000 difference scenarios.
Sentinel's database has grown considerably since its inception, and now includes data for nearly 200 million individuals and more than 350 million person-years of observation time. The data include administrative/claims data and electronic health records (EHRs) data provided by partners such as hospitals, insurers and universities.
Two recent additions include data from the Medicare Virtual Research Center, which significantly increases the data in Sentinel for patients over 65, and the Hospital Corporation of America (HCA), which represents five percent of hospital stays in the US.
The inclusion of HCA's data is a "game changer" for monitoring blood products, something the agency has struggled with in the past, as most transfusions take place at hospitals, said Steven Anderson, director of the Office of Biostatistics and Epidemiology in FDA's Center for Biologics Evaluation and Research (CBER).
Sentinel has already been used to study outcomes for a number of vaccines, including an ongoing assessment of adverse events related to Gardasil, and a planned study for Gardasil 9.
Marsha Reichman, senior advisor and scientific lead for surveillance programs in CDER's Office of Surveillance and Epidemiology, said that Sentinel could also be used to study the effects of switching between generic and name-brand drugs.
On the device side, Gregory Pappas, associate director for national devices surveillance at the Center for Devices and Radiological Health, said he envisions Sentinel as a "node in a network of networks" that form a national evaluation system for medical devices, but said unique device identifier (UDI) integration in EHRs and insurance claims forms remains a challenge.
Despite those setbacks, Pappas said that Sentinel could one day facilitate studies using data from patient registries, especially for implantable devices, that include the vast majority of patients with a particular device.