Although a booster dose of the COVID-19 vaccine increases immunogenicity in most patients with systemic autoimmune diseases (SAIDs), absent or suboptimal responses following booster vaccination may occur among those receiving immunomodulators, according to results of a study published in the Journal of Autoimmunity.
To evaluate immunogenicity following receipt of a COVID-19 vaccine booster in patients with SAIDs, researchers performed a prospective observational study at 21 centers in Italy. Immunogenicity was evaluated by measuring serum immunoglobulin (Ig)G neutralizing antibody (NAb) levels at the time of initial vaccination, as well as before and after receipt of a COVID-19 booster dose, which was administered at least 6 months after the first vaccine dose.
Overall, 478 patients with SAIDs were included in the initial analysis and matched by age against a group of 502 control patients from the general population. Of these patients, 344 were evaluated 6 months after initial COVID-19 vaccination and 244 were evaluated after receipt of a booster dose. Among patients in the SAIDs group who received a booster dose and those in the control group, the mean age was 62±14 and 59±14 years, and 16.8% and 27% were men, respectively. Of patients in the SAIDs group, 48 had seropositive rheumatoid arthritis, 16 had systemic lupus erythematosus, 155 had systemic sclerosis, 21 had cryoglobulinemic vasculitis, and 4 had other forms of systemic vasculitis.
The researchers found that serum IgG NAb levels among patients in the SAIDs group were decreased vs those in the control group at the time of initial COVID-19 vaccination (mean ± standard error of mean [SEM], 696.8±52.68 vs 1138±46.93 binding antibody units [BAU]/mL), with similar findings noted 6 months later (mean ± SEM, 370.8±41.92 vs 643.9±26.84 BAU/mL). Although patients in both groups had increased serum IgG NAb levels following receipt of a COVID-19 booster dose, the increase among those in the control group was statistically significantly greater vs those in the SAIDs group (mean ± SEM, 2470±10.74 vs 1527±74.16 BAU/mL; P <.0001).
The percentage of patients in the SAIDs group with absent or suboptimal immune responses decreased from 46.31% for responses assessed 6 months after initial vaccination to 7.8% after receipt of a booster dose. Despite this decrease, the percentage of absent or suboptimal immune responses after receipt of the booster dose was significantly increased among patients in the SAIDs group vs those in the control group (7.8% vs 0.2%; odds ratio, 0.02; 95% CI, 0.003-0.13; P <.0001). Of patients in the SAIDs group with absent (n=9) or suboptimal responses (n=10) after receipt of a booster dose, 100% and 70% were receiving immunomodulators, respectively.
According to the researchers, these “…findings indicate the usefulness of booster vaccine administration in patients [with SAIDs].”
Ferri C, Gragnani L, Raimondo V, et al. Absent or suboptimal response to booster dose of COVID-19 vaccine in patients with autoimmune systemic diseases. J Autoimmun. Published online July 11, 2022. doi:10.1016/j.jaut.2022.102866