The U.S. vaccine safety system still has gaps


By JoNel Aleccia, Kaiser Health News

Monday, May 3, 2021 (Kaiser News): The rapid detection of an ultra-rare blood coagulation reaction in some covid-19 vaccine the recipients showed the power of a federal alert system for vaccine security issues, but experts worry that the program’s blind spots may make it difficult to detect other unexpected side effects.

Before pandemic began, the Food and Drug Administration had downsized the program it successfully used to track adverse events during and after 2009 H1N1 flu pandemic, and the agency is still increasing its replacement, said Dr. Robert Chen, scientific director of the Brighton Collaboration, a global nonprofit vaccine safety net.

“It’s purely bad luck that they were between systems when they hit covid,” said Chen, who helped create the existing U.S. vaccine security systems for almost 30 years in the Centers for Disease Control and Prevention.

FDA officials acknowledged that some data analysis will not begin for weeks or months, but said the government is monitoring vaccine reactions with “state-of-the-art” systems.

“The FDA and CDC have robust safety and effectiveness surveillance systems in place to control COVID-19 vaccines authorized for emergency use in the U.S.,” FDA spokeswoman Abby Capobianco wrote in an email.

Undoubtedly, the country’s vaccine surveillance system worked as expected this spring when it identified unusual cases of blood clots combined with bass platelet It counts 15 people who had received the one-time covida vaccine from Johnson & Johnson, said Dr. Jesse Goodman, a former FDA chief scientist. Three people died.

“The good news for a very rare event is that it will appear on VAERS,” Goodman said in a call to reporters, referring to the vaccine adverse event reporting system, jointly managed by the FDA and CDC since 1990.

But other unforeseen and potentially dangerous reactions to vaccines may not be as evident in VAERS, a system that is believed to lose many potential side effects, or in the country’s additional control systems, including the US Datalink. vaccine and the new telephone monitoring of the CDC. program, v-safe.


“It’s a lot of different data collection systems,” said Dr. Katherine Yih, a biologist and epidemiologist who specializes in vaccine surveillance at Harvard Pilgrim Health Care. “It’s worth stating it’s not as good as it could be.”

The Vaccine Safety Datalink, while highly valued, did not include enough vaccines in its data from nine hospital systems covering 12 million people to detect the J&J problem, CDC officials said. And enrollment in v-safe has been lower than expected, with nearly 6 million people enrolled at the end of March, just 6.4% of people who had been vaccinated at the time.

This means that at a time when some 100 million Americans have been completely vaccinated against covid, the United States continues to rely on a network of vaccine control systems that can fail to monitor a wide range of vaccines. population, experts told KHN.

“I’m very concerned about that,” said Goodman, who also headed the FDA’s Center for Biological Assessment and Research (CBER) and is now a professor of infectious diseases at Georgetown University. “I think we should see this information about all these vaccines. Four months ago it was promised that it would happen. “

The three vaccines used in the US – produced by Pfizer, Moderna and Johnson & Johnson – have proven to be safe and effective during clinical trials of tens of thousands of volunteers.

But even the best rehearsals aren’t big enough to capture all the problems, especially the rare ones, if they only occur in certain groups or outside of a specific time period. It is important to monitor for side effects once vaccines have been distributed to the entire population (an effort known as pharmacovigilance) to ensure not only safety but also public confidence.

Vaccine safety experts said they were concerned that the FDA would reduce a system known as the post-licensed rapid immunization safety surveillance network, or PRISM, long considered a surveillance workhorse. .

“Before PRISM, I felt like we were in a dark time,” Steve Anderson, director of the FDA’s Office of Biostatistics and Epidemiology, said in a 2016 workshop. “When PRISM appeared, for us it changed from game “.


PRISM linked four major health plans to different parts of the country with eight state immunization records. During the H1N1 pandemic, it detected signs of three possible adverse events related to vaccines and was used to rule out the two unrelated and one, Guillain-Barré syndrome, that is.

The system included records of about 40 million people, said Daniel Salmon, a former director of vaccine safety at the National Vaccine Program Office. Having a large volume of vaccinated people records “really drives your ability to find out what’s going on,” he said.

PRISM, which was reused for drug safety, now contains data from about 60 million people, but has not been used to track vaccine reactions during the covid pandemic, said Salmon, who oversaw the control of H1N1 vaccine safety.

“With PRISM, we tested it in a crisis and it worked for a decade,” he said. “I was very surprised when it was not used for covid. That’s why we built it ”.

In 2017, a newer system, called the Biological Safety and Efficacy System, or BEST, was launched, but only recently did it begin monitoring weekly data from 15 predetermined adverse events among Medicare recipients. It will be expanded to include commercial databases from the end of June, according to Capobianco, the FDA spokesman.

The search for possible cases of the rare J&J vaccine-related condition began in mid-April and will be expanded in the coming weeks, he added.

FDA officials said PRISM’s capabilities have been incorporated into BEST, which can examine data from 100 million people. Experts told KHN that it has not been widely used to control post-vaccination effects, but Capobianco said, “We disagree.”

“BEST is built as an active surveillance system,” he wrote.

The concern is that officials have relied heavily on VAERS, a “passive” system that relies on reports from patients and health care providers to mark post-vaccination problems that may or may not be related to traits. A robust “active” surveillance system can search large volumes of patient care records to compare rates of adverse events in people who received vaccines with those who did not.


In addition, some vaccine safety experts point to the lack of clear authority in the area. The Trump administration shut down NVPO, a federal office with experience in controlling vaccine safety, by merging it with a government agency focused on infectious diseases.

As a result, surveillance for the safety of covida vaccines is fragmented among federal agencies, said Salmon, who now heads the Institute for Vaccine Safety at the Johns Hopkins Bloomberg School of Public Health.

“There is no one responsible,” he said. “You have to have someone at the helm.”

Biden administration officials have praised the country’s vaccine control system, noting that it marked Johnson & Johnson’s problems within weeks of the vaccine’s implementation. Federal officials stopped the distribution to assess additional cases and the next steps. (They were helped by the fact that European regulators had found similar problems in another vaccine.)

“VAERS acted exactly as intended in this case,” said Dr. Tom Shimabukuro, head of the CDC’s COVID-19 vaccine working group.

That’s right, said Dr. Steven Black, co-director of the global vaccine data network. However, he noted, there is room for improvement, especially more funding and better collaboration.

“This is a protection for our people,” Black said. “Whether for flu vaccines or coveted vaccines, we need to have a viable and strong system. Just because we think they’re safe doesn’t mean you don’t need systems in place to support that view. “

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