%0 Journal Article
%T Serologic Response and Safety after a Third Dose of the COVID-19 BNT162b2 Vaccine in Patients with Inflammatory Bowel Diseases.
%A Edelman-Klapper H
%A Rabinowitz KM
%A Zittan E
%A Bar-Gil Shitrit A
%A Goren I
%A Avni-Biron I
%A Ollech JE
%A Lichtenstein L
%A Banai-Eran H
%A Yanai H
%A Snir Y
%A Pauker MH
%A Friedenberg A
%A Levy-Barda A
%A Broitman Y
%A Ben Zvi H
%A Perets TT
%A Eliakim R
%A Barkan R
%A Goren S
%A Cohen D
%A Dotan I
%A  
%J Vaccines (Basel)
%V 11
%N 7
%D 2023 Jul 20
%M 37515078
%F 4.961
%R 10.3390/vaccines11071263
%X Vaccines are pivotal for control of the coronavirus disease (COVID-19) pandemic. Patients with inflammatory bowel diseases (IBDs) treated with antitumor necrosis factor (TNF)-α have lower serologic response after two COVID-19 vaccine doses. Data regarding a third vaccine dose are scarce. An Israeli multicenter prospective observational study recruited 319 subjects: 220 with IBD (79 treated with anti-TNFα) and 99 healthy control (HC) participants. All patients received two mRNA-BNT162b2 vaccines (Pfizer/BioNTech), 80% of whom received a third vaccine dose. Evaluation included disease activity, anti-spike (S) and nucleocapsid (N) antibody levels, anti-TNFα drug levels, and adverse events (AEs). All participants showed significant serologic response one month after receiving a third dose. However, three months later, the anti-S levels decreased significantly in patients treated with anti-TNFα compared with the non-anti-TNFα and HC groups. A correlation between serologic response to the third vaccine dose and anti-TNF drug levels was not found. No significant AE or IBD exacerbation was observed. Importantly, lower serologic response after the third vaccine dose predicted infection. A third dose of BNT162b2 is effective and safe in patients with IBD. Lower serologic response predicted infection, even in seropositive subjects. Lower serologic responses and their rapid decline suggest a fourth vaccine dose in this patient population.