IgG Antibody Responses Across 3 Doses of mRNA Vaccines

July 21, 2022

A study published in the Journal of Autoimmunity evaluated the immune response of Pfizer and Moderna’s mRNA COVID-19 vaccines in participants with autoimmune systemic diseases. Diseases included rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and cryoglobulinemic vasculitis.

In total, serum samples from 244 AD patients were collected 2-4 weeks and six months after their first vaccine cycle, and 2-4 weeks following their booster dose; 502 people from the general population were used as a control group. 93.7% and 6.3% in the AD cohort were vaccinated with the Pfizer and Moderna COVID-19 vaccines, respectively; this was comparable in the control group.

“Significantly lower levels of [neutralizing antibodies] were observed in the whole patients’ series and in the single [AD] subgroups at both time 1 and time 2, compared to the control group.” That being said, serum samples showed a sharp increase in antibodies after the booster dose, and the percentage of patients with no or suboptimal responses decreased significantly between the first and second check-in versus after the booster dose (from from approximately 28% to 46% – a significant rise in absent/ suboptimal response – down to approximately 8%). “The percentage of patients with absent/suboptimal response after the booster dose was significantly higher compared to controls,” which hovered at 0.2%. This was especially true for patients on immune-modifying drugs, including Rituximab, and glucocorticoids.

“The percentage of [AD] patients reporting one or more side effects within four weeks after booster administration was 40%; the side effects were usually mild and transitory. Remarkably, [AD] reactivation following the booster shot was observed in only 2% of cases although the events were invariably self-limiting.”