Anti-SARS-CoV-2 antibody responses are attenuated in patients with IBD treated with infliximab
Study of 6,935 patients with IBD treated with infliximab or vedolizumab (latter not linked to impaired immunity) found fewer infliximab-treated patients had detectable Covid-19 antibodies in their blood (3.4% v 6% with vedolizumab; P<0.0001), despite similar rates of infection.
Source:
Gut
SPS commentary:
Multivariable logistic regression analyses confirmed that infliximab (vs vedolizumab; OR 0.66; 95% CI 0.51 to 0.87, p=0.0027) and use of immunomodulators (0.70; 0.53 to 0.92, p=0.012) were independently associated with lower seropositivity. Among patients whose infection was confirmed, 48% of those treated with infliximab subsequently developed antibodies compared with 83% of those treated with vedolizumab (p=0.00044).
The authors acknowledge the limitations of the study; for example, it is not known whether attenuated immune responses for infliximab-treated patients translates into an increased risk of infection, and only humoral responses to infection were assessed. In addition, use of patient-reported data are subject to recall bias, and the prevalence of possible Covid-19 symptoms may have been underestimated. They caution that impaired serological responses to Covid-19 infection might have important implications for global public health policy and individual anti-TNF-treated patients, and suggest that serological testing and virus surveillance be considered to detect suboptimal vaccine responses, persistent infection and viral evolution, to inform public health policy.