- A new study shows that people with suppressed immune systems may benefit less from the standard 2-dose regimen of mRNA COVID-19 vaccines.
- The data suggest that vaccine effectiveness against COVID-19 disease and hospitalization may be lower in immunocompromised people.
- The degree of effectiveness also varies considerably between different patient subgroups, with organ transplant recipients having a lower level of protection.
- The study supports current CDC guidelines that say those who are moderately to severely immunocompromised should receive a third dose of mRNA vaccines.
There are many studies on the effectiveness of COVID-19 vaccines in people with healthy immune systems, but research in people with various immune-suppressing conditions is still limited.
Now, new research is helping to figure out just how protected people might be if they’re vaccinated — even if they’re immunocompromised.
A new study, published last week in the
But they goods even better protected than if they had not been vaccinated at all.
The study collected data from 9 US states through the VISION Network and analyzed 89,000 COVID-19-related hospitalizations between January and September 2021.
Scientists found that 2 doses of the mRNA vaccines were 77 percent effective against hospitalizations in immunocompromised individuals, regardless of age. By comparison, this figure was 90 percent for people with healthy immune systems (called immunocompetent in the CDC study).
The findings show that immunocompromised adults were less protected against serious illness.
Stefan Siebert, PhD, professor of inflammatory medicine and rheumatology at the University of Glasgow, said the results were in line with expectations.
“The main conclusion is that the [immunocompromised] were not so well protected [against COVID-19], according to the way they have defined vaccine efficacy. But what they found is that the vaccines worked, but not so well for immunocompromised,” he told Healthline.
He said it was reassuring that the number of vaccinated people who tested positive for SARS-CoV-2 was low. It was about 3.8 percent for vaccinated people, whether they were immunocompromised or not.
The study supported CDC guidelines, which say two doses are not enough for people with suppressed immune systems.
dr. David Hirschwerk, an infectious disease specialist at Northwell Health in New York, said the study was one of several reports reiterating the importance for immunocompromised patients to receive a third dose of the COVID-19 mRNA vaccines.
“The vaccines are generally safe and effective after two doses, but especially for people with compromised immune systems, the value of a third dose greatly amplifies the benefit,” he said.
Being immunocompromised means that a person has a medical condition or is undergoing treatment that suppresses the normal functioning of their immune system.
There are two types of immunosuppression. People can have primary immunodeficiencies from birth, or secondary immunodeficiencies that appear later in life. HIV, diabetes and leukemia fall into the latter category.
Medical treatments such as chemotherapy and oral steroids can also cause a person to develop a suppressed immune system. People with rheumatic and inflammatory conditions such as arthritis, lupus or Crohn’s disease who take drugs that suppress their immune system, cancer patients or organ transplant patients are included in this group.
These conditions or drugs can affect the performance of B and T cells, which are the building blocks of our immune response.
Therefore, immunocompromised people may not be able to respond vigorously to COVID-19 vaccines.
This means that people with suppressed immune systems do not produce the necessary amount or type of antibodies to fight SARS-CoV-2. Such people are more likely to get sicker with COVID-19, be hospitalized and suffer fatal consequences from the disease.
“These patients are [not only] at increased risk of COVID-19 due to their condition, [but] because of the immunosuppression, they can’t quite mount that immune response needed for full protection either,” Siebert said.
The researchers found that the vaccines’ effectiveness was lower in certain immunocompromised subgroups, namely solid organ recipients and stem cell recipients.
The study said they likely experienced a weakened immune response, reducing their protection to 59 percent.
Meanwhile, of all the immunocompromised subgroups analyzed, vaccine efficacy was highest at 81 percent for people with rheumatic or inflammatory conditions.
The rate was 74 percent for blood cancer patients.
For example, certain drugs, such as steroids or B-cell inhibitors, can negatively affect patients’ immune response to vaccination.
Siebert said the type or frequency of medication these patients take can also affect their level of protection.
The CDC study is consistent with previous findings from other studies and emphasizes the need for further treatment or preventive measures in immunocompromised groups.
A study by King’s College London found that nearly…
People with solid tumors also responded less robustly to vaccination compared to healthy individuals.
Antibody production also appears to be reduced in immunocompromised people.
One study found that only 25 percent of kidney transplant patients had detectable antibodies to SARS-CoV-2 after two doses of the COVID-19 vaccines.
Antibody titers, even when detected in the blood, are also likely to be lower in immunocompromised individuals.
A recent study of patients receiving immunosuppressive therapy for chronic inflammatory diseases found that these people had significantly lower titers compared to healthy controls.
But Siebert pointed out that a third dose won’t be a miracle cure.
“I think because of their condition or their treatments, no matter how many doses you give them, they won’t be able to mount that kind of immune response, or [reach] that level of protection,” he said.
He added that while the study can’t say definitively whether the third primary dose is the right strategy for all immunocompromised populations, it does say they need a little more.
Some doctors may advise their immunocompromised patients to take a break from their medication a few weeks before or after their dose to help the body build an immune response.
However, there is no consensus or evidence demonstrating the benefits of this or the correct timing.
“There is no evidence for it” [how to] balance between disease and protection. We kind of make decisions and collect evidence and try to act in real time,” Siebert said.
He explained that many of these drugs have long half-lives, meaning they can still be in the blood or body 2 weeks after pausing.
“So the reason for stopping the drug that will last 5 weeks and 2 weeks doesn’t make sense,” he said.
For some people, taking even a week off can trigger a flare-up, which can lead to more problems.
“I’ve had some people who haven’t had an eruption in 20 years, so they may be more willing to reduce [or stop their current medication], while I have had a number of people whose disease is still very active and difficult to control, and even a [week’s break] could be a disaster for them,” Siebert said.
He emphasized the importance of individual decision-making and acting on a case-by-case basis.
“The reason there’s no consensus is that one of the things that has consistently come up… [of research] is that having active disease increases your risk of [more severe COVID-19],” he said.
“[If you stop,] not only do you flare up, which in itself seems bad, but you’re also more likely to get steroids and other rescue treatments,” he added, highlighting the complexity of the decision.
Liu also reiterated that studies to date have not been able to specifically demonstrate any particular protocol to follow regarding pre- or post-vaccination medication,” except for the main point that [these] patients need a third dose.”
Siebert said current US guidelines suggest stopping the chemotherapy drug methotrexate, for example, 2 weeks before vaccination. This is largely based on data from flu, which showed that a break of several weeks prior to vaccination helped the immune response.
The British Society for Rheumatology, on the other hand, recommends that patients continue to take their regular medications.
“If you’re on a regular weekly drug or daily drug, the general feeling is that you shouldn’t stop taking it. There are always exceptions. But try to avoid steroids around the time of your vaccine.
— Dr. Stefan Siebert
Although the study included a more limited cohort and the median age of the patients was more than 65 years old, Hirschwerk said: “There is ample data to speak of the value of a third dose in younger immunosuppressed patients – especially those taking B-cell inhibitory cells.” get medication.”
Siebert advised immunocompromised people to limit the time they spend in indoor environments and crowded places as much as possible.
“The data for indoors and lack of ventilation is still huge. I’m not as concerned about my patients as they are [outdoors] in the open air or in smaller groups,” he said.
As for vaccines, he recommended immunocompromised people get their third primary vaccine dose unless there’s a medical reason not to get it.
“Then expect to get a booster 6 months later. Try to have common sense in an area with a high prevalence of COVID-19. The safety of social distancing [and] wearing masks will still be key,” he said.
He added that the vaccination status of those around you will also be a factor in making sure you are protected.
“They should be in consultation with their doctor about getting the third dose if they haven’t already. They should be careful about their exposure, that is, especially with [unvaccinated] people. If they are with people, it would still be best to be outside if possible, and people in their group could test themselves, as even immunized people can become infected and spread the virus if they don’t have symptoms.”
— Dr. Margaret A. Liu
“It’s all about minimizing risk while trying to live life. Masks and social distancing are still important,” Liu said.