Millions of people with compromised immune systems and their doctors are scrambling to figure out what to do in an evolving science project playing out in real time. Transplant patients and other immunosuppressed people often get less of a response from vaccines, but the results for the COVID-19 vaccine shots were particularly bad, according to a recent study by NYU Langone Health and Johns Hopkins Medicine researchers.

“Unfortunately, it’s not known what should be done. We don’t have data,” Mark J. Mulligan, MD, director of NYU Langone’s Vaccine Center, tells The Wall Street Journal. Dr. Mulligan says more research needs to be done into whether immunocompromised vaccine recipients are getting immunity in other ways besides antibodies, such as through their T and B cells, other actors in the immune system.

Robert Montgomery, MD, chair of surgery at NYU Langone and director of the NYU Langone Transplant Institute, was in the same boat as some of these patients back in March. Dr. Montgomery, who received a heart from a person with hepatitis C in a groundbreaking procedure, found out that he had no antibodies after two vaccine doses.

“We should be out in front of this, you know, rather than kind of leaving people to their own devices,” Dr. Montgomery says.

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