Children with IBD Respond Well to the Pfizer COVID-19 Vaccination, with Arthur Kastl, MD

A study presented at the 2024 Annual North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) Meeting in Hollywood, Florida, found children with inflammatory bowel disease (IBD) have a robust immune response to the COVID-19 vaccination.

Investigators were curious if children with IBD would respond differently to COVID-19 vaccinations compared to their healthy peers due to the frequent use of immunosuppressive therapies. The team sought to describe the clinical outcomes among those who developed a COVID-19 infection following a vaccine, the persistence of SARS-CoV-2 antibodies a year after vaccination, and the factors linked to the infection and the durability of the humoral immune response.

In their multicenter prospective cohort study, the team recruited patients aged ≤ 17 years who received ≥ 2 vaccine doses (97% who had antibody levels analyzed were on the Pfizer-BioNTech vaccine). Among 298 participants (50% male, 67% Crohn's disease, 20% ulcerative colitis, and 13% IBD-unclassified), 87% were on biologic therapy, including anti-TNFα (68%), vedolizumab (11%), ustekinumab (7%), JAK inhibitor (2%), and systemic steroids (6%).

Half of the participants (50%) developed a COVID-19 infection after vaccination, with 83% symptomatic. Participants on anti-TNF-a were more likely to develop symptomatic COVID-19 infection (adjusted hazard ratio [aHR], 2.7; 95% confidence interval [CI], 1.5 – 5.0; P = .001).

Children aged 1 – 5 years had a lower 52-week antibody level than older children (P = .04). Participants on anti-TNFa therapy also had a lower antibody level at 52 weeks (P = .007), as well as those who received only 2 vaccine doses before week 52 (P = .001).

Moreover, children who reported a COVID-19 infection before week 52 had a higher antibody level (median, 76.0; IQR, 38.0 – 144.0) than those who did not (median, 25.5; IQR, 8.8 – 76.0; P < .001).

At NASPGHAN, HCPLive spoke with Arthur Kastl, MD, from Children’s Hospital of Philadelphia, regarding the study’s findings.

HCPLive: Can you summarize the study?

Kastl: This is a multicenter study between 12 different hospitals looking at COVID vaccination and children with inflammatory bowel disease. There's a pediatric arm to this and also a large-scale adult arm—this abstract is only on the pediatric data. We had a bunch of publications from this, but this abstract right here is reporting on the durable immune response for the kids that were vaccinated [for] COVID and then also the efficacy of the vaccination as well.

HCPLive: How many papers have been on this topic thus far?

Kastl: On the pediatric side, this will be the fourth paper, and on the adult side, I think there's been 5 or 6.

HCPLive: What would you highlight as the largest finding from the study?

Kastl: The biggest takeaway would be that there's very reassuring information overall, that kids with IBD had a durable, protective, and immune response to [the] COVID vaccination, and that's shown by the very, very low rates of hospitalization that we saw in the population. [We] also [saw] that severe COVID following vaccination was quite low. There was a little bit of an attenuation of the antibody response to anti-TNF, but not enough that it translated into having a higher risk of severe COVID illness after [the] vaccination.

HCPLive: Did any of the findings surprise you?

Kastl: I don't think so. I mean, we had in the anti-TNF group where there was a little bit of attenuation that's been shown in a few other studies, so we weren't surprised to see that. And the other thing that we came across was the younger kids, being younger, being under age 5 or so, had a lower antibody level compared to older kids. But we suspect that that's partly because they had received a lower dose of the vaccine in general.

HCPLive: What potential directions for future research do you envision based on the findings of this study?

Kastl: I think the clinical arm of this whole study is coming to a close, but we have a lot of banked blood specimens from the cohort over the course of two years or so. So, I think it's going to move into a phase of more bench-related research, utilizing those blood samples to look at different types of antibodies across a number of different vaccines.

References

^{Kastl, A, Brenner, E, Weaver, K, et al. DURABLE IMMUNE RESPONSE AND LONG-TERM EFFICACY OF COVID-19 VACCINATION IN CHILDREN WITH INFLAMMATORY BOWEL DISEASE. Presented at NASPHGAN 2024 in Hollywood, Florida, from November 7 – November 9, 2024.}