COVID-19 mRNA-1237 weaker in patients with severe inborn errors of immunity

The mRNA-1237 vaccine against the coronavirus disease 2019 (COVID-19) retains good immunogenicity in patients with mild antibody deficiencies and phagocyte defects, reports a recent study.

However, in those with more severe inborn errors of immunity (IEI), such as combined B- and T-cell immunodeficiency (CID) and common variable immunodeficiency (CVID), the mRNA-1237 shot appeared to be less effective, with notably lower rates of seroconversion.

Researchers conducted a prospective, controlled, multicentre study of 505 IEI patients and 192 healthy controls, all of whom had received two doses of the mRNA-1237 COVID-19 vaccine. Outcomes included levels of SARS-CoV-2-specific binding antibodies, neutralizing antibodies, and T-cell response, which were assessed at baseline, 28 days after the first dose, and 28 days after the second dose.

At baseline, common types of IEIs were CVID, CID, X-linked agammaglobulinaemia (XLA), phagocyte defects, and isolated or undefined antibody deficiencies.

Twenty-eight days after the first dose, controls had a seroconversion rate of 97 percent. IEI patients with phagocyte defects (87 percent; p=0.10) and undefined antibody deficiencies (88 percent; p=0.11) achieved comparable seroconversion rates. In contrast, those with XLA (11 percent; p<0.0001), CID (71 percent; p=0.00024), and CVID (57 percent; p<0.001) had significantly lower seroconversion.

Such a pattern remained true until after the second vaccine dose. Those with undefined antibody deficiencies and phagocyte defects reached a 100-percent seroconversion rate 28 days after the second shot, as did controls. Meanwhile, XLA (15 percent; p<0.0001), CID (91 percent; p=0.012), and CVID (81 percent; p=0.0001) showed significantly weaker seroconversion.