PRISM Identifies Vaccine Safety Issues

By: Azadeh Shoaibi, Ph.D., M.H.S.

The word “prism” might make you think of a triangular piece of glass that separates white light into a rainbow of colors.

Azadeh ShoaibiBut at FDA, it means a powerful, computer-based system that separates critical bits of information from vast streams of healthcare data in order to investigate adverse events and determine if there is a connection to a specific vaccine. And while the FDA prism–called Post-licensure Rapid Immunization Safety Monitoring System (PRISM)—might not have such a colorful name, it’s a bright light in the agency’s continual efforts to identify adverse effects in a timely manner.

PRISM is a cooperative effort between FDA’s Center for Biologics Evaluation and Research and its partners in the health care and medical insurance communities. It analyzes health insurance claims data from four national healthcare plans: Aetna, HealthCore (Wellpoint), Humana, and OptumInsight (United Healthcare).

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PRISM is a computer-based vaccine safety monitoring system that separates out critical information from vast streams of healthcare data. A part of the Sentinel Initiative of FDA, PRISM broadens the agency’s ability to monitor critical healthcare products in support of its mission to protect and advance public health.

Since it was first inaugurated in 2010, PRISM has made valuable contributions to public safety.

For example, FDA was able to use the system to reassure the public that there was no link between an influenza vaccine and increased risk of febrile seizure in children (convulsion or seizure brought on by a fever). Another PRISM study comprising more than 1.4 million doses of Gardasil doses found no evidence of venous thromboembolism after vaccination among females 9 to 26 years old. FDA also used PRISM to identify a link between a rotavirus vaccine (RotaTeq) and an increased risk of intussusception in infants.

These case studies, along with other information, were discussed at a public meeting in December called to discuss what the system has accomplished and how it’s used in the regulatory process. The purpose of the workshop was to describe the Sentinel Initiative (a national electronic system for medical product safety surveillance) and the PRISM program, illustrate how FDA uses PRISM for regulatory responsibilities, and discuss the future direction of PRISM, including its further integration into the regulatory review process.

Stakeholders, including manufacturers, academics, the public, and other federal agencies, who participated in the workshop had an opportunity to weigh in with their opinions about the system, discuss its limitations, and offer ideas for improving it.

PRISM is one component of FDA’s Sentinel Initiative, which monitors the safety of a variety of FDA-regulated medical products by examining information in electronic healthcare databases.

Sentinel performs what is called “active” surveillance, as opposed to “passive” surveillance. Passive FDA surveillance systems depend on industry, consumers, patients, and healthcare professionals to recognize and report suspected adverse events to an FDA web site, such as the Vaccine Adverse Event Reporting System (VAERS). This means that FDA might not become aware of potential problems related to a licensed product for months.

Unlike passive surveillance, Sentinel’s active surveillance lets FDA initiate its own studies using existing electronic healthcare data in a timely manner. Sentinel also lets FDA evaluate safety issues in targeted groups, such as children, or to evaluate specific conditions (e.g., heart attacks) that are not usually reported as possible adverse events of medical products through passive reporting systems.

So by adding an active surveillance capability to FDA’s toolbox, Sentinel broadens FDA’s ability to monitor the safety of a spectrum of licensed medical products in support of the agency’s mission to protect and advance public health.

Azadeh Shoaibi, Ph.D., M.H.S., is the Sentinel Lead at FDA’s Center for Biologics Evaluation and Research

Another important step in FDA’s journey towards enhanced safety through full-scale “active surveillance”

By: Janet Woodcock, M.D.

They say the longest journey begins with a single step. In 2008, FDA launched the Sentinel Initiative and thus began a long journey toward the challenging goal of developing a full-scale medical product safety monitoring program using an important scientific technique called “active surveillance,” which complements our FDA Adverse Event Reporting System (FAERS). FAERS is already well developed and uses the equally important technique of “passive surveillance.” Today, I’d like to recognize our progress along the way.

Janet WoodcockAfter a successful five-year pilot program, which began in 2009, FDA’s Mini-Sentinel program is now transitioning, as planned, to the full-scale Sentinel System. I’d like to share with you the success of our Mini-Sentinel pilot program and some of FDA’s visions for our new leg of the journey toward full-scale “active surveillance” under the new Sentinel System.

First, a quick discussion of the importance of “active surveillance”: Over many years, FDA’s program that we now call FAERS has been our main tool for assessing the safety of medical products. This system relies on patients, medical professionals, and product manufacturers to report to us potential safety issues of the products FDA regulates.

FAERS is an invaluable asset, and we’re not seeking to replace it. However, the Sentinel System offers us the exciting possibility of not waiting for safety information to come to us in the form of reports, but rather it enables us to go out and get that information, adding greatly to our safety monitoring capability. This is active surveillance.

Over the past five years, the Mini-Sentinel pilot program has established secure access to the electronic healthcare data of more than 178 million patients across the country, enabling researchers to evaluate a great deal of valuable safety information. While protecting the identity of individual patients we can get valuable information from Mini-Sentinel that helps us better understand potential safety issues, and share with you information on how to use medicines safely. We have used Mini-Sentinel to explore many safety issues, helping FDA enhance our safety surveillance capabilities, and giving us valuable input in decision-making on drugs and vaccines.

We’re now well on our way to developing a nationwide rapid-response electronic active surveillance system, Sentinel System, for monitoring the safety of FDA-regulated drugs and other medical products.

So where does our journey take us from here?

  • FDA will build on the successes of the Mini-Sentinel Pilot. We have a variety of safety assessments ongoing under Mini-Sentinel that will continue and we will seek to expand our reach and capabilities with the Sentinel System;
  • Mini-Sentinel gave us an important start, but it is essential to continue to develop and refine existing scientific methods to evaluate the data we access through the Sentinel System;
  • We see Sentinel as a potentially valuable national resource for other safety researchers, besides those at FDA. Looking even further ahead, our hope is that, working with other scientific groups, we will be able to create a National Data Infrastructure that would enable other users (e.g., other governmental agencies, researchers from academia or industry) to access the Sentinel infrastructure for multiple purposes (e.g., medical product research, quality improvement);
  • Not only will such access directly serve the public health, it will also help sustain these programs because stakeholders will have an incentive to provide support (financial and otherwise) for its maintenance and growth.

From the outset, the goals of the Sentinel Initiative have been large and of ground-breaking scale. We knew it would be years in the making, but Mini-Sentinel’s successful completion marks important progress. We look forward to continuing and expanding our active surveillance capabilities as we now transition to the full-scale Sentinel program.

Janet Woodcock, M.D., is the Director of FDA’s Center for Drug Evaluation and Research