The following is a summary of the “Clinical Outcomes, Immunogenicity, and Safety of BNT162b2 Vaccine in Primary Antibody Deficiency,” published in the January 2023 issue of Allergy and Clinical Immunology by Milota, et al.
This study analyzed the clinical efficacy, safety, and time course of humoral and T-cell immune responses induced by the mRNA vaccine BNT162b2 in common variable immunodeficiency (CVID).
This prospective observational cohort study examined the effects of two doses of BNT162b2 on clinical outcomes (proportion of infected patients and severity of disease), safety (incidence of adverse events and changes in laboratory parameters), and dynamics of humoral (specific postvaccination and virus-neutralizing antibody assessment) and T-cell immune responses (detection of anti-SARS-CoV-2-specific T-cells) in 21 patients with CVID. After 6 months, the patients were evaluated again.
At 1 month after vaccination, 52% of patients (11 of 21) showed a positive immune response, but this percentage steadily dropped to 33% by 6 months (5 of 15). But their neutralizing antibodies against SARS-CoV-2 were significantly lower than those of healthy controls. Nearly 6 out of 13 CVID patients (46%) had a detectable T-cell response at month 1, and this response persisted throughout the study. Around 3 patients (14.3%) experienced a mild infection during the follow-up period. A good safety profile was also seen with the vaccine.
Although the BNT162b2 vaccine elicited a detectable antibody response in most patients, it was severely constrained by the absence of virus-neutralizing antibodies and the short half-life of antibodies specific to the anti-receptor-binding domain of SARS-CoV-2. Around 1/3 of patients showed signs of a T-cell response, which was relatively stable throughout the follow-up period. The clinical and safety outcomes of vaccination against severe COVID-19 are positive.