Vaccines Against Omicron Demonstrate Low Response Among Patients with IMIDs

Even after receiving 3 doses of the COVID-19 mRNA vaccines, patients with immune-mediated inflammatory diseases (IMIDs) did not generate mean cross-neutralizing antibody responses against the Omicron variant as they did against the original SARS-CoV-2 wild-type virus, a new study revealed.

“Many public health authorities stated that a third dose of the vaccine must be mandatory. This was under the presumption that recall responses led by booster doses increase the neutralizing antibody responses and consequently induce protective immunity,” the investigators wrote in the report. “Unfortunately, patients with autoimmune rheumatic diseases (ARDs) undergoing immunomodulatory therapies are excluded from COVID-19 vaccination trials, and there is limited data on immunogenicity of vaccines for the circulating SARS-CoV-2 variants of concern.”

The researchers examined the ability of COVID-19 vaccines to induce cross-reactive antibody responses against Omicron infections in adults with IMIDs (n=149) and health care workers as controls (n=94). About 68.5% of the total study population had received a third mRNA vaccine dose and none of the participants previously had COVID-19.

Average neutralizing responses and the mean response after booster shot for the original SARS-CoV-2 strain was similar between both groups. After second dose, the average neutralizing response in the IMID group was 76% and 72% in the control group. Following the third dose, the response in the IMID group was 97% and in the control group was 88%.

However, these numbers were very different when checked against the Omicron variant. The average cross-neutralizing response in the IMID group was only 11.5%, which rose to 27% after the booster. Only 39% of the patient sera showed neutralization of Omicron, even after the third dose. Meanwhile, the average cross-neutralizing response in the control group was 18% after the second dose and 50% after the third.

“Striking antibody evasion manifested by the Omicron variant in patients with ARDs and current vaccine-induced immunity may not confer broad protection from Omicron breakthrough infection, highlighting the need for further research on vaccine effectiveness in patients with immune dysfunctions,” the researchers concluded.

—Priyam Vora

Reference:
Kim W-J, Choi S-H, Park J, Song J, Chung J-W, Choi S. SARS-CoV-2 Omicron escapes mRNA vaccine booster-induced antibody neutralization in patients with autoimmune rheumatic diseases: an observational cohort study. Ann Rheum Dis. Published online: July 25, 2022. DOI: 10.1136/ard-2022-222689