There is a compelling case to support the implementation of COVID-19 booster vaccines for some people with a impaired immune system to help optimize antibodies to SARS-CoV-2, the scientists said.
The comments followed the results of a study that suggested that a significant proportion of patients at clinical risk with some immunocompromised or immunocompromised conditions mount a low or undetectable antibody immune response after two doses of a COVID vaccine.
Initial data from the observational cohort study T-cell antibodies and vaccine efficacy in the SARS-CoV-2 study (OCTAVE) were reported today in a prepress.
It suggests that about 60% of patients in the study groups presented an immune response that is similar to that observed in healthy control subjects. However, about 40% had a low or undetectable immune response.
The research, a UK-wide multicenter trial, led by the University of Glasgow and coordinated by the Cancer Research UK Clinical Trials Unit at the University of Birmingham, aimed to assess immune responses after COVID vaccination in people with immunity. mediated inflammatory and chronic diseases. These include inflammatory arthritis, kidney or liver disease, cancer, and patients undergoing a stem cell transplant.
Preliminary results
The first data, based on about 600 participants from a much larger cohort, were compared with those of 231 healthy people from the study of protective immunity against T cells in health care workers (PITCH).
The researchers reported that although all individuals tested in the PITCH study generated antibodies against the SARS-CoV-2 peak protein after two doses of the Pfizer / BioNTech or AstraZeneca / Oxford vaccine, only 89% of patients with seroconverted OCTAVE 4 weeks after a second dose.
Antibody levels depended on patients ’disease. The percentage of patients who responded less well than the lowest levels observed in healthy subjects was higher in those with:
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Patients with ANCA-associated vasculitis treated with rituximab (87%)
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Inflammatory arthritis (51%)
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Renal failure in hemodialysis and immunosuppressants (42%)
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Liver disease (36%)
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Renal failure in hemodialysis (20.3%)
The lowest levels of patients with low antibody reactivity were observed among patients with solid cancer (10%) and hematopoietic stem cell transplantation (17%).
Prof. Iain McInnes / SMC
Professor Iain McInnes, vice-chancellor of the University of Glasgow, who led the study, told a conference hosted by the Science Media Center: “Most patients in the OCTAVE trial have actually mounted an immune response that looks very similar. to a healthy control group “.
In addition, their results are compared with an “optimal group” of people who, on average, were younger than the OCTAVE cohort.
He also stressed that even patients who did not respond to any antibody after vaccination could be protected by a T cell response.
“We are quite reassured that even patients with fairly significant immune suppression regimens are mounting this cellular response, this T cell response, and this gives us optimism that there is some degree of protection against the virus, even for those with negative antibody levels. “
Study of the booster vaccine
Asked whether patients with impaired immune systems could benefit from a booster vaccine, Professor McInnes said: “Our data suggest that booster for people who have had an absent or lower antibody level be a very reasonable next step “.
Researchers had already begun a separate trial, called OCTAVE DUO, to address this issue, he said.
These would be randomized patients to receive the Pfizer or Moderna vaccine, with a small subgroup given a third dose as a booster with the Novavax vaccine.
“Comprehensive study”
Commenting, Dr Doug Brown, chief executive of the British Society for Immunology, described the paper as “one of the most comprehensive studies to date” on the subject.
He said: “As we find our way out of the pandemic, we must continue to investigate how to optimize COVID vaccination schedules for patients with impaired immune systems to maximize the future protection of these people.
“This includes examining whether booster doses would be helpful and studying other therapeutic options for the small minority of patients who cannot generate an immune response after vaccination.”
Eleanor Riley, a professor of immunology and infectious diseases at the University of Edinburgh, said the research showed that many of the patients in the OCTAVE trial “made a detectable antibody response and that their response returned to increase after the second dose of vaccine “. Therefore, it was “very possible that they had an even better response after a third dose of vaccine,” he said.
Examination of the immunological effects of COVID-19 vaccination in patients with conditions potentially leading to decreased immune response capacity: the OCTAVE process, prepress