IBD Patients Maintain Antibodies 6 Months Following COVID-19 Vaccination

Mazen Almasry, MBBS

Patients with inflammatory bowel disease (IBD) maintain levels of antibodies up to 6 months following 3 or 4 doses of mRNA COVID-19 vaccine doses.

A team, led by Mazen Almasry, MBBS, University of Wisconsin School of Medicine and Public Health, evaluated the sustained antibody concentrations of patients with IBD 6 months following the third COVID-19 mRNA vaccine dose.

The data was presented as a late-breaking abstract at the 2022 American College of Gastroenterology (ACG) Annual Meeting in Charlotte.

Response Rates

Past research has shown a reater than 99% response rate after 3 doses of the mRNA COVID-19 vaccine series in patients with IBD.

However, there is only limited data on the persistence of antibody levels following the 3 doses.

In the Humoral Cellular Initial and Sustained Immunogencity in Patients with IBD (HERCULES) study, the investigators evaluated the humoral immunogenicity of COVID-19 vaccines in patients with a diagnosis of IBD aged 18-85 years. Each participant was on stable doses of maintenance therapy for at least 2 months and had received 3 doses of mRNA vaccines.

The investigators measured serum SARS-CoV-2 anti-spike IgG antibody concentrations at month 1 (n = 180) and month 6 (n = 164) following the third dose of an mRNA COVID-19 vaccine.

There was also a small cohort of individuals who had a forth vaccine dose (n = 49).

Outcomes

The investigators sought a primary outcome of antibody concentrations at month 6 comapred to month 1 for those who had 3 COVID-19 vaccine doses.

They also sought secondary outcomes of the effects of immune modifying therapies on sustained antibody concentrartions and previous COVID-19 infections, as well as antibody concentrations at month 6 in the 4 dose group compared to the 3 dose group.

The investigators found 98.7% (n = 162) of the 3 dose group had measurable antibodies at month 6, while all 49 patients in the 4 dose group had measurable antibodies at month 6.

However, the antibody concentration level was 31 mcg/mL in the 3 dose group at month 6, compared to 77 mcg/mL at month 1 in this group (P <0.001).

There was also trends based on medication type for IBD.

For example, patients treated with anti-tumor necrosis factor (anti-TNF) medications had lower antibody concentrations compared to patients not treated with anti-TNFs (median 20 mcg/mL vs. 35 mcg/mL; P = 0.001).

The team also found prior COVID-19 infections resulted in a higher antibody concentrartion (median 189 mcg/ml vs. 24 mcg/ml; P <0.001), while antibody concentrations were 98 mcg/mL at 6 months in the 4 dose group, compared to 31 mcg/mL in the 3 dose group (P <0.001).

“Almost all patients with IBD had measurable antibodies six months after a third dose of an mRNA COVID-19 vaccine,” the authors wrote. “Antibodies were also present in all of those who had received a fourth dose. Those on anti-TNF therapy had lower antibody concentrations which is consistent with prior studies.”

The investigators suggested future research should monitor responses to additional doses and the expected bivalent vaccines.

The study, “45 - Persistence of Antibodies Six Months After Three COVID-19 mRNA Vaccine Doses in Patients with Inflammatory Bowel Disease (Late-Breaking Abstract),” was published online by ACG.