Patients treated with infliximab for inflammatory bowel disease (IBD) showed significantly reduced response to COVID-19 antibodies, compared with those treated with vedolizumab, according to data from nearly 7,000 patients.
Dr. Kim L. Isaacs
Although anti–tumor necrosis factor (anti-TNF) drugs are routinely used for patients with IBD, the impact of their immune-suppressing properties on protective immunity to COVID-19 is unknown, wrote Nicholas A. Kennedy, MD, of the University of Exeter (England) and colleagues. These drugs have been reported to impair protective immunity following vaccines for other diseases, such as those for influenza and viral hepatitis.
“By suppressing immune responses, biological and immunosuppression therapies may lead to chronic SARS-CoV-2 infection and have recently been implicated in the evolution and emergence of novel variants,” they noted, citing a study published in Cell.
In the current study, published in Gut, the researchers used data from the CLARITY IBD study to identify 6,935 patients with IBD aged 5 years and older seen at 92 hospitals in the United Kingdom between Sept. 22, 2020, and Dec. 23, 2020. Of these, 4,685 were treated with infliximab, and 2,250 received vedolizumab. The proportion of study participants with a positive anti–SARS-CoV-2 antibody test was the primary outcome, with secondary outcomes including proportion with positive antibodies following positive polymerase chain reaction test for SARS-CoV-2 and the magnitude of antibody reactivity.
Substantial seroprevalence differences seen
Overall, rates of symptomatic and proven SARS-CoV-2 infection and hospitalization were similar between infliximab-treated and vedolizumab-treated patients with IBD. However, seroprevalence was significantly lower in the infliximab group, compared with the vedolizumab group (3.4% vs. 6.0%; P < .0001). In addition, infliximab and immunomodulator use were each independently associated with lower seropositivity, compared with vedolizumab (odds ratio, 0.66 for infliximab and OR, 0.70 for immunomodulators) in a multivariate analysis.
In a sensitivity analysis, 39 of 81 infliximab-treated patients with polymerase chain reaction–confirmed COVID-19 infection seroconverted (48%), compared with 30 of 36 vedolizumab-treated patients (83%) (P < .00044). Infliximab-treated patients with confirmed infections also showed a lower magnitude of anti–SARS-CoV-2 reactivity, compared with vedolizumab-treated patients (P < .0001).
From a clinical perspective, the lower seroconversion rates and reduced levels of anti–SARS-CoV-2 antibody reactivity might increase susceptibility to recurrent COVID-19 infections in infliximab-treated IBD patients, the researchers noted. In addition, the impaired serological responses might promote chronic nasopharyngeal colonization and consequently promote the development of COVID-19 variants and drive persistent transmission, the researchers said.
The study findings were limited by several factors including lack of knowledge on the impact of attenuated immune response on infection risk, the potential for recall bias associated with patient reports, and the focus on infliximab only, the researchers pointed out. However, the key findings are likely apply to other anti-TNF monoclonal antibodies including adalimumab, certolizumab and golimumab, they suggested.
The study was strengthened by the recruitment of a large number of patients in a narrow time frame and comprehensive collection of data on patient-reported outcomes, COVID-19 testing, and serological assay results, the researchers said. Overall, the findings support the public health value of serological testing and virus surveillance to identify suboptimal vaccine response and to consider implications for practice, they added. “If attenuated serological responses following vaccination are also observed, then modified immunization strategies will need to be designed for millions of patients worldwide,” they emphasized.