NIH to study COVID-19 vaccine effectiveness on patients with compromised immune systems

The National Institutes of Health announced on April 23, that it is launching a study to assess how people with compromised immune systems respond to COVID-19 vaccines.

The study has already begun enrolling participants at the National Institutes of Health Clinical Center in Bethesda, Maryland, the NIH said. It will be a single-site study with up to 500 people enrolled, 400 of whom will have primary or secondary immune system disorders and 100 without such conditions. 

The study will be led by researchers at NIH’s National Institute of Allergy and Infectious Diseases (NIAID). 

Dr. Anthony Fauci, the nation’s leading expert on infectious diseases and the director of NIAID said, "Through large Phase 3 trials, several experimental COVID-19 vaccines were shown to be safe and effective and three are now authorized by the U.S. Food and Drug Administration for emergency use in the United States."

"People with immune disorders are typically excluded from trials of experimental vaccines, and this was the case in the COVID-19 vaccine trials. This new study will characterize the features and adequacy of immune responses to COVID-19 vaccination in people with a range of immune deficiencies and dysregulation syndromes and will provide valuable information about benefits and potential risks in these individuals," Fauci continued. 

Previous research has raised questions about how well COVID-19 vaccines protect people with compromised immune systems. 

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A study published on March 15 by researchers at Johns Hopkins University looked at how COVID-19 vaccines specifically protected organ transplant recipients. Transplant recipients take powerful immune-suppressing drugs to prevent organ rejection, which also increases their risk from the coronavirus.

Vaccines rev up the immune system to recognize the virus, something that’s harder to do if someone’s immune cells aren’t in good working order.

For the Johns Hopkins study, researchers tested 436 people who had received new organs in recent years and were getting the Pfizer or Moderna vaccines. A few weeks after the first dose, 17% of the transplant recipients had developed antibodies against the coronavirus, said Dr. Dorry Segev, a Hopkins transplant surgeon who co-authored the study.

Of most concern were people whose transplant medications included a type called an anti-metabolite. They were far less likely to respond to the shot than those who don’t require that kind of drug, the study in the Journal of the American Medical Association said.

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The findings came after the U.S. Centers for Disease Control and Prevention said fully vaccinated people can relax some, but not all, of the masking and distancing precautions against the coronavirus.

Dr. David Mulligan, Yale University’s chief of transplant surgery and immunology, said the study was a disappointment but not a surprise because people with weak immune systems don’t respond as well to other vaccines.

Some transplant groups, including the American Society of Transplantation, already have issued cautions about that.

As for the most recent NIH study, scientists say they hope to better understand how people with immune deficiencies respond to COVID-19 vaccines. 

"Currently, there are few published studies on the incidence and clinical presentation of COVID-19 disease in people who have immune deficiencies, especially those who have inborn conditions involving deficits or dysregulations in antibody or cell-based immune responses to infections," said study principal investigator Emily Ricotta, Ph.D., MSc, of the NIAID Laboratory of Clinical Immunology and Microbiology. "Our study aims to fill this knowledge gap."

This story was reported from Los Angeles. The Associated Press contributed.